personally, I don't think there is enough mario (who wouldn't want 3 2D mario's in a single generation?), but maybe that is just me.
However, if there is to be more Mario I want quality titles like Strikers. Mario Party was ok, but could have been vastly improved upon and it wouldn't have been that hard. Also, two of the Mario games are actually Sega games, so you can't really count them, as they aren't Nintendo Mario games.
Anyways, my collection only has 6 out of 26 titles that are actually "mario" games. I had 5 out of 22 on the GC. And the best thing is, that they are typically some of the best games I own on the console.