Here's an interesting challenge. A Fate/Extra crossover with Sword Art Online.
Let me give you the premise of Fate/Extra. During the 2030s, humanity has become obsessed with virtual reality games (I can't remember the acronym for it). Magecraft and magic have faded, leaving nothing left. However, a new type of magecraft is created, allowing magi to hack into computers with their Magic Circuits. All is fine until a major company finds a unique super computer on the moon, which has the ability to grant wishes. The supercomputer hacks into every computer on earth, changing it forever. It then decides on who should get its power by taking the souls of those with the ability to hack it, magi, and staging a Holy Grail War.
In Sword Art Online, the setting is in the 2020s and virtual reality game fan-bases are growing at an exponentially fast rate.
In this fic, I recommend using Kirito as the main character, as we don't know who is parents are or what they even did. I'd say to make his dad secretly a mage and to have his parents killed off by Enforcers. Also, when picking out a Servant I recommend either Saber Arturia Pendragon, Rider Medusa, or Archer Nameless (EMIYA).