I actually like pretty all of them. The N64 ones are dated, but I won't hold it against them. The Strikerses are really good. Toadstool Tour is relaxing. The Game Boy RPG-type ones are incredibly addicting. 3-on-3, while a bit frustrating at times both in difficulty and controls, is really creative and a lot of fun. Sluggers is great (though you may want to ignore the story mode), and has almost enough characters to satisfy me. DDR:MM has some pretty cool music and a really good difficulty range for me. MASATOG is a bit disappointing, but not horrid by any means.
Best: Mario Tennis GBC
Worst: Mario Pinball Land, if that counts. If it doesn't, then no vote. I honestly can't think of a single Mario sports game that I don't like.
It's still not a cameo in Alleyway, despite the fact that Sqrt2 seems to think that whoever wrote that it is on the game's page on the main site has the final word on the matter.
The only way it's not a cameo is if it's a full-fledged Mario game. And it's not. Unless you also want to say that Pinball, Tennis, and Punch-Out are Mario games. It's true that there are no other characters in the game besides Mario, but it's not a character-based game, so that's not a significant observation. Mario is thrown in as an afterthought.
Look at it this way: If a puzzle game has all the blocks falling down from the top of the screen the whole time, it's a falling-blocks game. But if a FPS has a block fall on you in one level, that doesn't make it a falling-blocks game, even if that falling block is the only block in the whole game.
