So this is currently the best map we have of Chemical Plant Zone from the Sonic 2 Nick Arcade prototype:

(Full resolution - you can almost see where to go)
Any chance of a proper full size one? And indeed, proper full size ones for every map in the prototype? And other prototypes?
Here's one category.
I kind-of feel we should be doing better than one map from the Simon Wai prototype after nearly 20 years, and even this one is missing objects (although it's a lot better than nothing!).
My plan is to get some more thorough game comparisons on the wiki. Perhaps a handy dandy template that can flip between prototype and final maps on the fly. Something better than what we have now, which is nothing at all. I mention this now because I'm in the process of merging some of the old SWS2B/S2B content into the main wiki proper, and we've got a set of small maps that aren't as helpful as they could be.
btw this isn't just Sonic 2 - the layout changes between Sonic 3 and Sonic 3&K aren't documented either. Nor are those early Sonic 3D prototypes where there's all this extra space, or Knuckles in Sonic 2, or anything from the Chaotix or Sonic CD prototypes - there's quite a lot we're missing. Some maps we do have were also shrunk down due to technical reasons back in the day - I don't think those limitations exist anymore (Egg Gauntlet here is 23,000 pixels long and the wiki seems to be coping).
Oh and also maps you might think are redundant, such as Genocide City Zone. It might end up coming out as a big empty rectangle but it's good to see exactly how empty it is. And leftover maps such as Hidden Palace in Sonic 2 final - eeeeeveeerything.
The only missing maps you don't need to worry about are the randomised chunks for Blue Sphere - they're still queued up on the server waiting for a switch to be flicked.