I would love almost every single Nintendo developed game become playable on Switch in some form or other. There are a lot of third party games too.
I'll try to keep it to around 10 here so I'm not here forever :P
Super Mario Galaxy 2 - My second favourite game of all time, how did they not include this in 3D-All Stars?
Ocarina of time and Majora's Mask - An HD upgrade of the 3DS versions would be amazing.
Twilight Princess and Wind Waker HD - I mean.... just port them... they'd sell just as well if not better on Switch
Xenoblade Chronicles X - one of the last Wii U games that needs a second chance on Switch
F-Zero GX - would look fantastic with just a resolution bump
Sonic Colors and Sonic All Stars Racing Transformed - 2 of my favourite games ever
A Link Between Worlds - Honestly, lets just say every Zelda game. ALBW is my favourite 2D Zelda hands down