I'm not really sure where Regina got the idea that life in Storybrooke would be a particularly effective punishment, and neither is she.
Regina, if she stops to think about it, rather wishes she had better investigated the exact nature of the Land Without Magic before casting the Dark Curse. She understands why she did not consider it—a heady and burning mix of bloodlust, grief, and desperation, with bloodlust featured prominently—but as the years in the Land Without Magic stretch on (and on, and on, and on again, unchanging)... Regina doesn't enjoy the sensations of regret, and does her best to squash it at ever opportunity.
To be sure, there are many opportunities. The Huntsman (he's called Graham, here) still serves her, but he does so willingly, and with an almost touching mix of roguish charm and hesitant sweetness. There is no hatred in his eyes when he looks at her, no misery when she touches him, and Regina is the first to admit that tight jeans, buttoned shirts, and slender neckties suit him at least as well if not better than his heavy furs or guard uniform. (The regular showers he takes here are also a distinct advantage.) The Blue Fairy and her flock of sparkly bugs are well out of the way in a convent, forbidden from meddling. The foolish Prince sleeps, and this never fails to make Regina smile (anyone else would have called the expression a smirk) when she thinks of it: she may have failed to curse Snow with eternal sleep, but in this world Snow's husband suffers what should have been her fate. They call it a coma and explain it away with science, but Regina can still relish the irony of it. All those who opposed her in the old world are now subject to her rule, frozen in time with faint, false memories of dull lives they never truly lived (though the curse seems to have had a sense of humor in assigning them roles in this new world, and all that's changed about the cricket is that he is a man again).
Best of all, Snow White has been transformed from a disobedient, treasonous, deceitful little wench to the meek, fearful, downtrodden, ill-paid Mary Margaret Blanchard, who cringes if Regina so much as looks at her. It takes a long, long time to tire of the little squeak of fear the woman wearing Snow White's face makes when Regina passes her by on the street, or comes to her classroom on some insignificant errand.
Even in this there is dissatisfaction, however. Mary Margaret, for all her shyness, for all that she cowers in this world as she never would before, remains sickeningly optimistic about absolutely everything, and besides, what kind of torment is being an elementary school teacher? True, being trapped in a room for six hours a day with a pack of unwashed, easily-bored children isn't a fate Regina would wish on her worst enemy, but Snow, gallingly, has taken to it remarkably well. Regina reads the newspapers in the Land Without Magic. She knows that there are so many ways in which Snow's life could be worse. Eternal separation from her true love and the erasure of her personality are all well and good, but Miss Blanchard is hardly suffering. She has enough to eat, decent friends, a comfortable apartment, and a job she enjoys. Regina could have done so much more.
Rumpelstiltskin is another thorn in Regina's side. She watches him on the streets of Storybrooke, where so many look on him with terror, and wonders idly why exactly she honored their deal to give him a good life in the new world. Even in the Land Without Magic, where he is nothing more than an aging pawnbroker, his name arouses more fear than hers ever will. He could have been made to suffer. He could at least have been made to fear her, rather than the other way around.
Regina banishes these thoughts as soon as they are born, but they keep coming back. Perhaps soon she will do something differently, test the limits of her victims' memory loss and see what she can do that they will be forced to forget here. The possibilities are nearly endless, even without magic. It is still her curse. It is still her vengeance. It is still her victory. And it is enough.
It has to be enough.