Phantasmagoria would be really cool.
Still one of my favorite part.
I still remember the earlier Touhou games (6,7,8,...).
They all had so many different features.
And then ZUN started with MoF and it became so featureless.
Luckily than UFO started with some more features again.
Still, I'd like to have game with new and lot of features.
Though Phantasmagoria would also be cool.
Also, I hope that ZUN someday will release a part (maybe a fighting-part), where they're all extra stage bosses, playable.
This way, no one would be TOO strong, to put into the game.
Oh, and few features like re-watch the endings. (Always making me furious, if I wanted to check an ending again)
And maybe also a function to fast-foward the music, in the music room (sth I just urged for).
BTW, just noticed that th14 is not connected to th13, story-wise.
Well, I haven't finished playing yet, so don't tell me if there's a connection in story.