I really hope Rocket League stays far, far away from Switch... Because it has all the trappings of something I would get very addicted to!
Assault Android Cactus is another good shout yeah, they were developing a Wii U version for a while I think, but it kept getting postponed. That final boss is absolutely brutal!
Could also imagine Severed being reworked with motion controls instead of stylus swipes, if the Joy-Con are truly precise enough? You'd have to make the hits land harder to not tire out players, but I see potential.
That said, I'd rather we see new indies instead of established ones or reworked ones. Would rather see something new cooked up by Drinkbox, Nifflas, Image & Form, Witchbeam, or the people behind Nova-111 than see (enhanced) ports.
Things like Snipperclips, while being a Nintendo game, are exciting precisely because they're new things on a new console (imo).
EDIT: oh aren't the people behind FTL working on something new based around Pacific Rim? Probably won't make it to Switch I guess, but it'd be cool.