I'll help as much as I can with the redesign, however I don't know how much I'll be able to help with it. My designing forte is creating large, mainly stone structures.
This video here shows the kind of stuff I think I'm best at building in Minecraft (at around
6:44 the actual build shows up).
I think that I'll be able to help with designing whatever the next iteration of the grand plaza will be, probably some of the house variants for the town, and possibly an entrance to the mansion. Other than that, I probably wouldn't be very good at designing anything, though I'd be happy to do any building needed provided adequate instructions. I'll try to provide any raw materials that I can.
Hope I'll be helpful, Salt/Pillow.