Sin & Punishment is JPN exclusive, the only way to play it in the US is to either use an illegal device or download the virtual console version. You have Goldeneye, you don't really need anymore 007's.
Harvest Moon is pointless if you have Animal Crossing on any system, it's not that great to begin with.
I would recommend getting all 3 Mario Parties, Mario Golf, and Mario Tennis. There's also Kirby 64, as well as the two Pokemon Stadium games.
I'll toss another vote for Space Station Silicon Valley. Had a'lot of fun with it as a kid, but I dunno if it's still great today. You're selling Pokemon Snap, I think that is a wise choice as that game has not aged well; It was a small phenomenon when it came out, and maybe even a year or two after release, but the original cartridge is worthless as you can download the virtual console version, which has the ability for you to take in-game photos and save them to your Wii!
F-Zero is the type of game that you're either going to hate or love, and I'm unfortunately a hater. I suggest trying a demo or seeing some videos before buying.
As far as numbers, I think 20-25 is an acceptable number. I personally am aiming for 20, with the only real exclusions being the Zelda games, as Ocarina of Time has the 3D version, and Majora's Mask is getting a 3D remake eventually as well. Keep the cartridges though, no reason to sell them if you already have them.
If you really don't feel like you enjoy Killer Instinct and DOOM, then by all means get rid of them or give them to a friend or family member. Trust me on this, if you don't feel motivated to play a game, then don't keep it around unless it has some sort of practical use(Like having multiple versions of a Pokemon game for more save files).
There's collecting for the sake of collecting, and then there's collecting to play. Which are you?
