The GC had better quality graphics than the PS2, was made more efficiently as well. The result - Metroid Prime graphics completely surpass the graphics ever seen in any PS2 game - there's no jagged edges to be seen and the quality is superb. Its on par with the XBOX console.
The only thing the GC disappointed me in was the lack of many good quality third party games apart from retro studios... The controller I found was far more comfy than the PS2 and XBOX, the graphics were good quality and the console was very light compared to the other consoles. PS2 didn't have four port multiplayer because it was more focused on the lone gamer playing a FPS game or a sports game.
Speaking of FPS, I used to enjoy playing them in games like Doom, GoldenEye, Halo etc. Then I got bored... why? FPS are essentially all the same except for the storyline and the type of monsters you have to kill. And all you pretty much do is run around shooting anything that comes in the way.
On another post IMO a really good shooter would be Turok... It is a bit of a cross between FPS and adventure. That game had one of the coolest fog effects I've ever seen in a FPS game. The background music was good as well.