Maybe locations from fangames would be cool to have, like the big plum tree from Mystical Power Plant or the planetoid Pluto from The Last Comer. I apologize for being new and throwing these thoughts out already.
I'm sorry, this doesn't seem like the type of thread for this idea. Do you know which thread's the one I can suggest things in?
I always thought that place was a big bomb waiting to go off rather than a castle. Like, a big underground chamber with a dangerous orb of magic energy in it with a ceiling of tiles and glass windows (you can see the orb in Stage 4 and while fighting Mima). Or maybe even a big globe floating in the sky or half of it encased in the ground with an orb of energy in the middle.
The castle is really cool, though I wish the mini-sun had a bigger emphasis.
Hi, nice to meet you all. I'm new here, but I'm very impressed with the work you've all done on the Minecraft Gensokyo thing. I'd even go so far as to say it's one of the fandom's seven wonders.