For essentially $100 I could not pass it up. I have been wanting to play more of Mario Maker and that alone made it worth it for me.
Donkey Kong and Mario Kart are on my radar.
If you like WRPGs then get Xenoblade (technical it's a JRPG but plays like a WRPG)
If you like high action Devil May Cry games then get Bayonetta
You like multiplayer platformers that you can player with your friends then get Mario 3D World
Mario Kart is very fun (even if you're not into racing game)
Splatoon is very fun (even if you don't like shooting games)
There's also Smash Bros (but personally I'm not into it)
If you like Mario Maker then you'll probably like Minecraft or whatever it's called.