Thanks for the thread link.
Gonna check it out now, oh and before I forget... SonicWorldsDeltaV1.2c.7z to stop hotlinking (may be used as permanent link if need be). Also, can't wait to see this new build. It'd be nice to see a fresh layout too considering the amount of times I've seen this same layout over and over again.
If you could make it so it has a sense of depth it looks much nicer since the perspective of the water does not fit the mountains at all. It makes my eyes confused when trying to distinguish the distance of the farthest water and the far green/mountains. Try some gradients with light blue to dark blue. This will give it some more depth. Also, sticking to a similar colour scheme may help. Maybe try looking at some official Genesis pallets.