This almost completely. I've noticed that the bosses survive longer on higher difficulties too, and there's more popcorn spam, and Lily shows up less (maybe due to Lv. 4 spam) and scoring is higher.
Also if you do go for lunatic I'd suggest Marisa because a friend of mine who spammed attempts with Komachi and Reisen cleared it in 4 tries with Marisa-and I got it in 4 tries with Marisa as well after failing about that many times with Reimu.
Of course if you just want a 1cc you can't beat using Aya (except you have to fight Medicine....ugh....)
Except you don't start off with Aya unlocked. You only have Reimu, Sakuya, Marisa, Youmu [Who sucks horribly, seriously her charge time...], and Reisen until you've beaten the game.
And, yeah, I generally die on Stage 6, 7 and Komachi, regardless of character or difficulty. [Well, I've not tried Easy...]
I looked at one of my replays, the the things the AI pulls off... wow. At one point, unless I missed something, it also clearly
cheated, because Medicine was surrounded by Sakuya's Lv 3 spell, cornered, and without chargeing my spell, and some nearby random danmaku, vanished ._..
Considering she charged for a Lv 4 spell right afterwards dosen't help the case.