My two cents:
Theres 2, possibly 3 sections in the demo that are extremely difficult, if not downright bullshitty:
1)Ringos last spell. Yeah, sorry. This spell is fun, but it really feels a bit WAY too much RNG based. I think ZUN needs to nerf the bullet amount- Not much, just a tiny bit. Maybe that will fix it...
2)That first laser + aimed bullets section: I am not fully sure if this either falls on Bullshit or just extremely difficult... TBH the more and more I try it, the less BS it seems to be. I am even getting semi-consistent at doing this part, when I get to it I usually can pass it in around 10 tries on average so it is not TOO bad... Probably...
3) That one 3rd boss spell thats like some sort of ribbon... .just what. Well, it probably has some sort of gimmick to it, too soon to tell. But I always bomb this one because I just got tired of seeing "Story: 0/99+" below the spell name, LOL.
Other than those, I think the difficulty is fairly obviously harder than other Touhous, but nothing TOO insane... That begin said, for the final version, if the other 3 stages are going to just keep going up in difficulty... Well the game could benefit from begin a bit more resouce happy tbh.