The ones I believe would benefit most are:
Super Mario Maker - This one is just plain obvious
Bayonetta 1 + 2 - Bayonetta 2 is an amazing game and porting it to the Switch would be a good idea so that more people could have an opportunity to play it. Especially if they make Bayonetta 3
Tokyo Mirage Sessions - Give this game more light. It's a fantastic RPG, and one I believe many more would enjoy playing.
Xenoblade Chronicles X - Same reasons as the ones above. It would be a great filler title too.
Super Smash Bros? - As for this, I believe all they really need is to add a shit ton more characters, stages and a small story mode. They already have the base game from the Wii U, and if they added all of those other things, I think it would be acceptable. But a new game is also welcome.
And if they make a Wonderful 102, add the first game with it.
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