Just happened upon this, did a playthrough, and found I liked it quite a bit.
Just a few gripes, namely that clipdeath seems to happen quite a bit, and that the first few stages and bosses seem quite a bit longer than they should be... Even if you don't want the game to start off slow, you have to start out small so it can build up over the course of the game. This also gives the player a chance to build up resources early on, which in turn allows you to make the later parts of the game even harder. It also allows people getting used to a new shot type to ease themselves into the gameplay. However, since you haven't coded in power items ala CtC, it's acceptable to have the first stage's trash fight back a bit, heh.
I'm just going to throw this out there, but I've 1cc'd every Touhou game on hard mode with the exception of UFO, 1cc'd lunatic on IN and LLS, beaten every extra stage in the series(including PoFV's 2 extra scenarios, StB's extra tier, and Phantasm), and done a plain and dirty clear of Subterranean Animism on Lunatic.
It took 4 continues for me to get through this game on Normal.
I think you've confused "harder than most Touhou games" with "harder than Seihou Banshiryuu".
The reduced hitbox size and restored point item generation will hopefully help alleviate some of this difficulty, however.
With gripes on difficulty and difficulty curve out of the way, some thoughts on the art and backgrounds:
The sprite artwork put me off a bit at first, but I quickly got used to it. One thing that I really loved were the cartoony backgrounds; from the eerily bright and patterned night sky of stage 2 to the white barracks of stage 4, I drank it all up...
The character art could have been better(particularly Rika's braids; just how much hair gel did she have to put in for them to stick out like that?), but no serious complaints. Some of the bullets looked off(the PCB-ish arrow bullets and the bubble bullets in particular).
I got a kick out of the story, but I was left guessing how an "artist from the human village" was somehow flying through the sky. Stage 4 continued the wallbanging over flight with Rikako floating in the air without her jetpack. And while we're at it, Rika should have a floating platform to stand on. I'm probably the only person who cares, anyways.
Dialogue was great. Stage 1 midboss dialogue went on a bit long, but stage 2 seemed to have gotten it right. Stage 4, in difficulty(even by this game's standards), atmosphere, and story content felt like stage 5, and when the actual stage 5 rolled around, the Kotohime encounter felt like a step down.
Finally, music. Boy oh boy, I loved the music in this game. The soundtrack downplayed the Touhou inspiration of the music to create original songs that just happened to move into the territory of the tunes from the series the game is based on.
However, it should be noted that the tracks don't have any built-in loops, and as a result I've had the music end and then start back up again from the beginning. You didn't even include the full "she's in a temper" track, and I've had that file reach the end during the dialogue after the joke fight! In order to ensure that this doesn't happen, you have to make the track long enough so that the player can time-out most(if not all) of the attacks before the music ends... but given how large that would make the files, it would be best to offer the music as a separate download from the rest of the game. Hell, that's probably a good idea even if you don't put loops in the tracks.
So yeah, I liked it... but I'm wondering where 5.5 is at the moment, since it was apparently supposed to be released 2 months ago. :V
