The only game on that list that is cheap is Shovel Knight, and I wouldn't buy that game for more than $8, and like I said, I'd rather get that type of game on 3DS. All the others are way over priced. They'd need to be $20 for me to buy them this far after release. And that's on the eshop. I don't do retail.

Sarcasm?

Easily Rayman Legends! The level design in great, the presentation is top-notch and the game is simply the definition of multiplayer madness!

Yeah, definitely Rayman Legends. 

Tropical Freeze hands down.
Best visuals, most refined gameplay and the best music.

Donkey Kong Country Tropical Freeze, fun, challenging, everything a 2d platformer should be, is my favourite game on the system

Stealth 2. I´m in love with that game. Best use of the touchscreen in multiplayer so far. Great puzzles.

havnt had the time to play DKCTF just yet but I am deeply in love with both Rayman Legends and Shovel Knight. Big fan of SMBU as well but havnt put that many hours in to it just yet.

As of right now I'd say Rayman but I am sure it will be Donkey Kong when I have tried it, they have always been my go to games when it comes to platformers

New Super Mario Bros. U.

It is the only one I have though, so there's that, but I do genuinely think it's a good game. The best of it's series, because of the world, that's for sure. Maybe if I'll play Tropical Freeze I'd think that one is better. I might still get that game some day, but I'm not that familiar with Donkey Kong. I only have the original on SNES (did play the second too) and Donkey Kong Land on GameBoy. I don't like Rayman's mechanics period so that's not it either.

I've played all candidates except Shovel Knight, and from them I would pick NSMBU. Still impressed with the multiplayer added on the Wii, plus that connected overworld is a joy to discover the shortcuts. And was surprised by the challenges with consecutive jumping/bumps sections in there - even the gamepad ones!

Rayman's gamepad is smartly used, but it's non-existant on Donkey Kong. It's nice to see Stealth Inc 2 pop-up a few times in the thread, been thinking on getting it; although I must wait for the mandatory eShop sale!