While the GameCube controller is far superior to its unfortunately-nerfed and gimmicky and dysfunctional successor, it's still nowhere near as good as it's hyped up to be - it's not really dual-analog, for one, and the lettered-button size is completely out of whack. Giant A, small B, X and Y buttons above those that are bean-shaped and easy to confuse. The C-stick is tiny and uncomfortable and use, and the d-pad...ugh.
Nah, I'd much rather take the Wii U GamePad over it, though the Wii U Pro Controller is still king.
Additionally, the usage of mini-DVDs or whatever the format's called really limited the size of GameCube games, compared to PS2 games. This is something the Wii arguably does better, but most of that worthless trash's releases are shovelware and inherently-borked garbage, so it wouldn't be truly fixed until the Wii U.
The GameCube does have the best console Pokémon games ever (I'm being serious - Genius Sonority knew what they were doing, and Shadow moves had the physical/special split going before it became cool), and the best original 3D Legend of Zelda games ever (though TWW HD and TP HD made them mostly better, aside from needlessly cutting the length of the Triforce hunt and Sacred Tears hunts, the two originated on the humble GameCube), too. Oh, and while I've never played these next two games, Pikmin and Pikmin 2 are both inarguably better here than they ever were on the next gimmicky dysfunctional console ("New Borked Play Control")
However, it doesn't have Super Paper Mario or Pikmin 3 or Xenoblade Chronicles 2 or Okami or Super Mario 64 DS or Pokémon Black 2 or Ace Attorney or Professor Layton.