I always kind of assumed Collision Chaos was the bit where Sonic ascends the chain, despite the absence of any chain to ascend - Amy isn't captured until that point in the game (despite some manuals saying she was kidnapped before Palmtree Panic), and the whole upside-down-land-at-the-top-of-the-level thing sorta lends itself to that theory as well (though which side is Never Lake/Earth and which side is Little Planet is ambiguous - I always figured upside-down was Little Planet, but I can't provide any evidence to support that). Though what it is beyond that, anything that'd justify all the bumpers, flippers and neon signs everywhere... I dunno, your guess is as good as mine.
ITS A POWER PLANT THATS FURTHER AND FURTHER IN DEVELOPMENT NEXT TO A SHITTY DOWNTOWN AREA Where the bad future seems to be nasty coal or oil or other mass pollution, the good future seems to be hydroelectric with plants than help with oxygen production. The big spinning log is actually a turbine. Completely immobile in the past, kind of in motion in the present, and spinning fast, generating energy in the future. I can't make sense of the obstacles and other set pieces but they're probably there just to be analogous with SYZ Makes the most sense imo The past is the innocent piece of land that gets I AM AN UNFUNNY SHITSTAIN turned into said power plant
If boiling it down simply, I think of a mix of urban city with jungle gym/pinball-inspired scenery and aesthetics. But this is pretty much how I perceived Spring Yard Zone, though I find Collision Chaos a bit wackier and funkier in music.
I always thought that the "land in the sky" was the result of vertical background scrolling combined with too vertical a level layout. Isn't there a similar effect during the pseudo 3D ramp sequence in Palmtree Panic 1?
The structure in PPZ is a loop, not a ramp. They were going for this. Can't apply to CCZ unless gravity is being warped somehow. And just for kicks, you can also see that inside loop effect applied a bit more readably in Silhouette Mirage and this Dezaemon game.
I'd say Collision Chaos seems a lot like a flashy, colorful, and overall crazy kind of acid trip where you hope to god that you don't land in the flustered pack of bubbles near the end of Act 2 and immediately get hit by a bed of spikes, making you lose your chance at a special sta-wait, where am I going with this?