I haven't heard much good about Lost World so you may wanna skip that one.
You really don't need to buy MKWii. MK8 is better in pretty much any way you could imagine. NSMBW and NSMBU are totally separate games and one doesn't really "outclass" the other, per se.
Brawl also probably won't need to exist after Sm4sh comes out.
Personally, I'm not the biggest fan of the Zelda games bar ALttP (and ALBW by extension). At the very least, I think OoT is overrated as all hell; as much as people like to say that it's a great game, it becomes relatively dull by modern standards if you remove the nostalgia goggles. ALttP being 2D helps it escape that trap. On WWHD: I think I've posted about this before (maybe complained on irc?) but if you're going to make a port, it really isn't enough to just make it prettier (clay graphics in dark areas also show where the graphics are genuinely worse than the original game), add in an item that makes getting around a bit faster (behind RNG and not just built in), and remove a tiny bit of tedious backtracking. Recent updated ports from Nintendo have more or less been acts of desperation; attempts to quell people's yearning for new games with nostalgia instead of real content.
Might as well make a "if you have nostalgia buy this" category for SSB.
There's a couple of random Wii games that would be nice to buy if you're into them / can obtain them in the first place. Off the top of my head I can think of the New Play Control! Pikmins (which afaik are stupid rare though), Rhythm Heaven Fever (literally about 10$ for a stellar game), Warioware Smooth Moves, and Zack and Wiki.
Oh, and Donkey Kong Country Returns is pretty different from DKCTF. The SNES DKCs are also pretty good games (DKC2 is filled with bullshit regarding how it hides secrets but if you're not OCD about 100%ing it you'll be fine). I personally enjoyed DKCR more than TF (I don't know why, but something about the tone is off in TF) but that's really a matter of personal opinion and (I imagine) one of those "whichever you play first you like more" type of things. Maybe that's also my own nostalgia, idk.
There's more VC stuff I have to look up since I don't remember for the life of me what I bought way back when.