So, I've had Sonic Colours, and been playing it, for a week now. I think I'm ready to place it on my "favourite Sonic games" list:
1. Sonic 3 & Knuckles
2. Sonic Colours (Wii)3. Sonic CD
4. Who cares? Those three are on a different tier.
This game is fantastic. The environments are varied, and all have surreal aspects to them. The music is some of the best I've ever heard. The story is well-written, well-voiced, and all-round well. The gameplay is truly Sonic Colours as I imagined it. But despite how awesomely high I rate this game, I still have a few complaints:
1.

Stop this shit.
I don't want to run in a straight line for ten minutes occasionally moving left and right to avoid lasers. It's boring. So is the Inceptor. I liked Racing Motobugs in the one Asteroid Coaster act dedicated to them, as it served as a nice pace-breaker from the other acts, and was very short. Would've been nice if they'd stayed in that one act, though. Would've been better if there'd been a full level there instead.
For this reason, I don't like Terminal Velocity Act 1 - it's a full level of laser and Interceptor dodging. This may seem like a contradiction to that above, but this has two main differences. Interceptor dodging isn't as cool as Racing Motobugs, and the level was a hell of a lot longer.
Terminal Velocity Act 2 was different, though; it's almost just a playable cutscene, and kinda reminds me of such things as being able to control and hit Robotnik at the end of the original Sonic the Hedgehog. It fits perfectly into the level, and story, as it is. Also, it's short.
2.

There are these fantastic environments, full of hills and valleys and general flow. Why, then, does the platforming look like this?

Remember, SEGA, Sonic levels are like women: better with curves.
Also, some more 3D platforming wouldn't go amiss either.
3. Remember this?

Yeah. This is how you do 2-player. Sonic Colours' 2-player mode is better than none at all, but split-screen is greatly preferred. It'd be nice to play REAL levels 2-player too, rather than just Sonic Simulator stages.
4. Less autoplay. I understand that almost all Sonic games have moments where the game plays itself, but this has a few too many. I'd like if they were kept to about 20 seconds MAXIMUM per ZONE (ie about 4 seconds an Act, on average). There's only one time I've been truly accepting of a long autoplay moment in this game...

... because it was awesome.
5. Stop reusing bosses. The first three bosses are awesome. The second three bosses would be awesome were it not for the fact that they're the same three bosses.
... And that's about it. Everything else I'm pleased about, or at least not bothered. That's my two cents, and now I'm going to go home and play it again.
EDIT:
QUOTE (GeneHF @ Nov 19 2010, 02:50 PM)

Where? All I can find is the path you slide under by the spring (which is technically going backwards), the small hole where the Spikes Wisp is, and the place where batbots are. I couldn't really find another path since Wisp use it forbidden.
Hit the spring. Walljump up the section the spring leads you to.
This post has been edited by DigitalDuck: 19 November 2010 - 10:18 AM