The 3D is just fine, its the gameplay that's broken. Some slick Camera work can give us the same perspective and keep Sonic looking cool. Having story is fine, the only thing is the story is supposed to serve the action, not the other way around.
I don't think Team Sonic understands how to make 3D racing, which is essentially what sonic does, exciting and engaging. And their bosses, at least the ones of the past ten years, are laughable.
Here's what they need to do to fix this up.
1) Make Sonic Faster
- More Speed, silky smooth framerate, sonic should be the fastest videogame characater, and newbies should be able to lose control of his max speed and plow into some spikes they didn't see coming.
2) Give Sonic options when running
- Most important: a jump that doesn't kill all momentum. This is the one thing that broke the 3D games or than anything. You could give a tap and hit the next platform moving. It was just another thing to slow sonic EVEN MORE! Also, a sidestep and a slide for obstacles/tackling enemies. Being able to Airdash into a run, run straight up walls, even if you don't have enough momentum to get to the top.
3) Give Sonic more challenges while Running
- This is the hard one, the most important. Instead of stopping Sonic to fight x, y, and z, let the environment and its valid hazards be the challenge, instead of just a static track. Let the stops be quick for a skilled player, a bop on the head (instead of a slow chain dash). Up the ante with moving challenges and threats. It's one thing to go through a level, another to go through the same level with RoboSonic chasing you down.
4) Fix the camera, and the boss fights, and the storyline and...
- The camera has been horrible, imho. It has to be more intuitive. Bosses seem uninspired, still doing the three soft spot hit with a waiting pattern. A general lack of insight and creativity mars the series now. It needs all around more quality and polish, even if the speed comes back.
That's all, keep your stories, your extra characters, your whatever. If you speed sonic up, and get him back to running and cannonballing animals free, maybe throw in some wisecracking like on the cartoons, the game will be good, you'll get old fans and new.
Short version: Stop Slowing Sonic Down.