Sonic Generations: Beaten! I then went back to try out the new awesome ability the game gives you, followed by fighting Metal Sonic to Sonic Boom because...seriously, that's how the fight SHOULD have been!
Silver was a nice fun fight, Egg Dragoon not so much. Egg Dragoon wouldn't have been so bad if the fight didn't take forever to kill; not only does he take a lot more hits than any other boss in the game, but he's only open during specific moments that can be easily missed, and the fight gets monotonous, and the falling section really just gets obnoxious.
The Final was...rather unfun. Not that Super Sonic Final Bosses have been all that fun to begin with, but this was especially boring. S Ranking it attempt #1 means that I must have been doing everything right though <_<
Overall...game is just great. The fact that the Sonic Fanbase is bitter about this game just shows how unpleasible they are. It IMPROVES Classic Sonic style with better controls, less glitches, more intuitive physics, etc., and has the best of Modern Sonic, and is a perfect representation of the series from the original game through Colors. Furthermore, the ending credits managed to outdo Dissidia in terms of Nostalgic Fan-service, and that's no easy feat. I really can't find a reason to say this is anything but the best the Sonic Game ever.
That said...
Best Classic Stage: Gonna go with Crisis City. Its hard and stylish, and really makes you work, but never feels STUPID about it. Its exactly how difficulty should be handled.
Worst Classic Stage: Seaside Hill. Besides the cool Whale bounce thing, this stage offers nothing. Its a bland attempt to basically put Aquatic Ruins/Hydro City/etc. in the game with a different paint job, and has nothing going for it. Its not difficult (though not trivial), and unoriginal.
Best Modern Stage: Rooftop Run or City Escape. City Escape is impressively faithful to the original version despite that not being a Modern Sonic Game, which just goes to show how Sonic Adventure 2 really was "Proto-Modern Sonic" in terms of style, Rooftop Run is just very well done, and stylish, and NOT a carbon copy of the original (which they totally could have gotten away with, because that was a really damned fun looking stage in Unleashed and Unleashed uses the same style as Modern Generations.) Honorable mention to Crisis City because damned was that impressive how they made that FUN.
Worst Modern Stage: Seaside Hill again. See, the Classic Era Sonic stages were cool to see the adjustment into Modern style, what with Green Hill Zone's FISH CAVE or the Exploding Chemical plant, the others were faithful adaptations of the originals (or flat out immense improvements in Crisis City's case), then we have...this stage, which offers nothing but a go cart section that is mostly a MACH SPEED section but less interesting.
Best Boss: Shadow. Stylish, uniquely designed, and really everything a rival fight SHOULD be. Silver and Metal Sonic weren't bad by any means, shadow is just exceedingly good.
Worst Boss: The Final. Poorly done Super Sonic style boss, as I said.
Best Contribution to the game: Even Sonic Adventure 2 or Sonic 2k6. City Escape and Crisis City are great, and both games contributed fun rival boss fights. I think I'll give 2k6 the win here just because "Holy shit they made Sonic 2k6 LOOK GOOD" which edges out the Shadow fight or something.
Worst Contribution: Sonic Heroes. Having the worst for both style stages, and adding nothing else, there's really no contest. and its not the home game's fault either, because Sonic 2k6 is easily the worst game they used of the 9 and well...see above <_<
Oh, I will say this:
While I was disappointed with Planet Wisp being Sonic Colors stage, I will say the stage (both styles) was well done and it surprised me they actually incorporated THAT mechanic into the game. Nice little treat.