After the dust of Hogwarts settled everyone realized that things were not, and would never be, quite as they had been before. Nearly everyone would admit however, now with Voldemort gone and his Death Eaters either on the run or captured, that things were bound to get better than they had ever been in the near future. A great memorial was held at Hogwarts Castle, it was attended by so many from the Wizarding World that people spilled from the top towers of the castle, into the great hall, throughout the grounds, and some even spilled into the Forbidden Forest. A great plaque was set into the newly rebuilt wall of the castle, right next to the entrance. The plaque listed the names of everyone who took part in protecting the castle from Voldemort, the names of the deceased were laid out prominently towards the top of the plaque, with one name set out a bit more prominently than the others which read:
Severus Snape
For no one gave their life as completely as he.
Flitwick placed a charm upon the names so that whomever looked at the name of one of the deceased and had ever interacted with that person were instantly reminded of their most favorite memory of that particular hero. Hogwarts, of course, reopened the following year.
Xenophilius Lovegood died soon after the fall of Voldemort, though before the end he was visited by his daughter's three good friends, who all forgave him for any past indiscretions which may have occurred. His daughter, Luna, took over as editor of the Quibbler. In order to boost subscriptions, Luna went on another expedition seeking the Crumple Horned Snorkack. Acting on an anonymous hint from a reader, Luna finally located a herd of live Snorkacks, living peacefully in Alberta, Canada. The front page of that special edition Quibbler features a beaming Luna sitting astride one of the Snorkacks with Dean Thomas waving from beside her. The tiny signature under the picture in the Quibbler read: Dennis Creavey (who had taken up photography in tribute to his brother).
Neville Longbottom had never felt more appreciated by his family than he did after the Battle of Hogwarts. Even his old gran had to admit that he could do things with a plant that she could never dream of. Therefore, when Professor Sprout retired after the battle to open her own magical greenhouse to seek some quiet, no one objected when Neville was offered the post of Herbology professor. Indeed, he was the youngest person ever to be allowed to teach at Hogwarts. That fact, coupled with his renown valour and great selflessness at the Battle of Hogwarts, made him a very famous man. He was never one to seek the spotlight, however, and therefore he lived alone for many years after the Battle, immersing himself in his teaching duties, until he was invited to a close friend's birthday party and was introduced to a charming, beautiful young woman, freshly graduated from Beauxbatons and who was looking to improve her English. Less than a year after Neville and Gabrielle, who only ever afterwards had eyes for him, married.
Kingsley Shacklebolt was put into place as interim Minister of Magic after the battle of Hogwarts. He was officially elected shortly thereafter by an almost unanimous vote. Shacklebolt went right to work getting the Ministry back on it's feet, albeit it with a couple changes. House elves, Goblins, Centaurs, and Muggles were all given their own official liaison offices to the Ministry.
For the first time in magical history, house elves had representation on an equal par with witches. A very respectable and sensible house elf called Winky became the first representative of her kind. She was always impeccably dressed, except for two curious objects that she wore but never satisfactorily explained. One was a folded down sock which was quite garish to behold, she only ever said that it was left to her by a very good friend. The other object that Winky sometimes wore to very important Ministry meetings was a small badge pinned to the front of her smart dress shirt which simply read S.P.E.W. When asked about the meaning of this badge, Winky would just smile softly and not speak a word.
The Goblins took advantage of their newfound status to demand the return of all Goblin made objects. It is not too much of a surprise that many witches simply could not locate the priceless objects that the Goblins sought which had been handed down thru their families, and so they had to sadly inform the Goblins that they would not be handing that particular object over.
The Centaurs took to dual representation, the first two being the great Centaur Firenze and the dark Centaur Bane. They hardly ever left the Forbidden Forest, preferring instead to communicate by messenger service. The Ministry was only too happy to provide them with a messenger by the name of Dolores Umbridge, whom existed to keep the centaurs happy and to perform their every whim.
Owing to the fact that very few Muggles indeed ever knew that they had a liaison office with the magical community, a representative was appointed in their stead. His name was Arthur Weasley, and it could never be said that he had anything but the best intentions towards Muggles as he performed his job. Perhaps the single greatest Act that he managed to push through the Ministry was the Hogwarts friends and family Day. Each year on October the 31st, the Hogwarts Express would appear at Platform 9 and ¾. For this day only, Muggle-born witches' family and friends could slide through the barrier, board the gleaming train, and spend the day at the castle with their sons, daughters, cousins, nephews, nieces, friends, and so on. The very first time that the Hogwarts friends and family Day took place, in the very first compartment of the train sat a boney, horse-faced woman, her lips pressed tightly together and her handbag clutched tightly in her hands, but with the brightest twinkle in her eyes. Next to her sat a rather large, yet kind faced young man who could not hold back his delight when the snack trolley came to call. When confronted with the question, and the very real danger, of how to keep all of these Muggles quiet about one of the Wizarding worlds greatest secrets, it was Arthur Weasley who said, quite simply, that he could not think of any charm or memory wipe that was better suited to keep the Muggles silent save their love and concern for their relative at Hogwarts.
George Weasley said, many years afterward, that forevermore he always felt as though a piece of him was missing. Many people who did not know him just assumed he was referring to his one absent ear. Above the register of every Weasley's Whizarding Wheezes (of which there are many) presides a laughing portrait of Fred, who is known to still chip in a good gag idea every now and again. George's first new product design after the battle of Hogwarts was a sort of glittery purple paste. If this paste was put on a wall, anyone near enough would be frightened by the illusion of the wall collapsing in on them (especially good for making teachers believe that you are not out of bed, they are merely having a weird nightmare). He named it after his brother, and thought that he would have found it delightfully amusing. Lee Jordan bought into the business as partner to George and helps him in research and design.
Percy Weasley remained at the Ministry for several years, reveling in the new administration because there were many new rules to put into place. After a while though, as Percy spent more and more time with the expanding Weasley family, he decided the Ministry was not really for him and he went to work for George in the joke shop. George described Percy's responsibilities as 'all the boring paperwork and regulations that could only concern a dreary git'. Percy did try to contribute to the joke shop with his own ideas, he was always interviewing young Hogwarts students on their thoughts about his projects. Eventually, George relented and let Percy put his 'Leaky Cauldrons' into production (cauldrons that would leak their contents if anyone but their owner were to touch them, good for discouraging copying).
Rubeus Hagrid remained gamekeeper at Hogwarts long after the children of his favorite Hogwarts students had come and gone. He took only one year off, and that was to help Gwap find a wife and a new home in the mountains. Hagrid finally found a lifelong companion in Madame Maxine who gave up the headmistress post at Beauxbatons to fill a new teaching position at Hogwarts: no longer Muggle Studies, but Studies of Other Non-Magical and Magical Ways of Life (which included Muggles, Goblins, House Elves, Giants, Trolls, and Centaurs).
As for the rest of the Weasleys, Bill and Fleur lived a happy life at Shell Cottage. They both continued to work in Gringots and had girls, Victoire and Amelie. Charlie returned to his dragons and never married, preferring the dragon's company to that of a female. Mrs. Weasley continued to dote and fawn on all of her children, and also on the many grandchildren that would come in the following years. All of her relatives loved to tell the tale of her duel against Bellatrix, though she claimed it was nothing and always changed the subject (lest her children use her behavior in the duel as an excuse for future dangerous acts). Ginny went on to finish school at Hogwarts, after which she played chaser for the Holyhead Harpies, Slughorn always used to boast that it was he who introduced Ginny to Gwenog Jones. After a few years on the team Ginny decided she had had enough of the Quidditch life and married Harry, then went on in her father's footsteps and worked at the Ministry in the Magical Games and Sports Department.
Some other quick notes: Professor McGonagall took her rightful place as Headmaster of Hogwarts, which she held for almost 30 years. Mundungus Fletcher went on to create trouble for himself for many years, until it is said that he crossed a goblin the wrong way and went into hiding somewhere in northern Russia. Aberforth lived out his life as the barman at the Hog's Head. Seamus Finnigan, Cho Chang, the Patil twins, and most of Harry's other Hogwarts students went on to live normal wizarding lives. Goyle never recovered from the shock of the Room of Requirement fire and was sent to St. Mungo's. Lucios Malfoy paid for his crimes in wizard prison until he was a very old man. Draco, however, went on to become headmaster of Durmstrang's, and to his credit, toned down the dark arts taught at that school and always had excellent relations with Hogwarts.
Hermione helped Harry clear out dementors and dark wizards from the world (after she had lifted the charm on her parents, who really had fallen in love with Australia and decided to stay, though were delighted to find out that they had a daughter). When McGonagall became Headmistress of Hogwarts, Hermione was offered the post of Transfiguration professor and she accepted. She was never too busy to have private chats with Winky on how elf rights were progressing. Hermione finally ended up asking Ron to marry her, as she thought he would never get around to it, and they were married and continued the Weasley tradition of having copious amounts of children with red hair. None of them ever had to wear second hand robes. Many years later, when Ron got his own chocolate frog card, it listed his many achievements as: auror, one of the trio who defied Voldemort and brought about his downfall, the inventor of 5D wizard chess, and an accomplished ballroom dancer.
Harry Potter spent several years helping to track down any death eaters who had escaped. After this task was finished, he refused an auror position and a place at Hogwarts as Defense Against the Dark Arts professor. He preferred to spend his middle aged years spent quietly with Ginny and his children. Over the years, he wrote several books, the first a biography of Dumbledore which he hoped would clear his name, the second detailing his journey to destroy the horcruxes. When all the children had grown and Ginny was becoming tired of working at the Ministry, he finally relented and accepted the position of Defense against the Dark Arts. Later on he became headmaster of Hogwarts school, always turning down the post of Minister of Magic that was continually offered to him.