I might be going out on a limb but I want to see Soul Calibur VI come to Switch. Yes, it'll be cheap on PS4 and Xbone by then, but I would really like playing it on Switch. Would be cool to add Nintendo characters like Link, Lucina, Marth, or Ike into the game (and not custom-related). SCVI runs on UE4 so it would be interesting to see how it translates to Switch.
Besides SCVI..I think Tokyo Mirage Sessions #FE, Persona, Ultimate Marvel vs. Capcom 3 (I would've said MvCI but....), The Last Story, Xenoblade 1 and X, Bioshock, Portal, Borderlands, and the Mass Effect original Trilogy would be great on Switch. Of course, there are other titles that could possibly work out on Switch, but these are several that I can think of at the moment.