Mario Kart is funky!
Mario Tennis is lovely!
Mario Strikers is kicking! (Lol pun intended.)
Some other Mario Sports game which isn't quite established as a series + compliment!
The Wario Platformers are teh awesomez!
The Yoshi Platformers are teh awesomez!
Well, there are two Mario Paint games, so I guess that counts.
The WarioWare series is groovy as heck.
You started mentioning other character games before Mario Party!?
The one you forgot. (Other)
Personally, I don't think games with "Yoshi/Wario" in the title count as Mario spin-offs.
*Poll option reserved for Meat Puppet*
... I hate Mario.