I must say that I'm on the fence and can't decide between Sonic 3's, Heroes' (minus plastic head Sonic), and Generations' styles. I guess I can't decide between them because they are very similar. Sonic 3's is my favorite of the Genesis games and is just simply classic. Heroes' looks like an updated version the classic style (IMO), but it is held back by occasional cheap plastic looking objects at times. And Generations looks like an almost perfect modern interpretation of the classic art style. So far, it looks like Generations will most likely become my favorite Sonic game of all time. That is, atleast in terms of art direction.
I think Sonic 3D Blast had pretty nice art. Say what you will about the rest of the game, but it looked pretty good. Dat Rusty Ruin Zone. But my favorite art direction definitely goes to Sonic 1. The simplicity of both the shapes and the colors really make that one stand out to me.
This is also my favorite art style of Sonic. I just really admired Sonic Adventure 2 artwork, where he's holding back a dark chao with his finger while staring at Shadow. I liked it when I played Sonic Riders. Everybody had this anime look with this striped darkness to the less important parts. It was original and it looked cool. Amy and Rouge had a new uniform and it's a great design, but no else had anything new except for one or two accessories. It wouldn't hurt if Sonic had a space suit costume like he did in SA2B and had a track number on it. What made me disappointed is that they didn't keep it up when the Zero Gravity was introduced. Now this Babylon place is actually from outer space instead of being some awesome Magic Carpet-inspired place.
