Hey there, just tested the game.
Thanx for reply

I'm currently working on a final version of this stage completely rebuilding it from scratch, so expect more stuff, especially on hard mode.
Hitbox: I have no problems with it's size - just something different for the Touhou-only players to get used to. I do think it would be a good idea to show players where and how large the hitbox is though. If you don't want to have the hitbox glowing every time the player focuses, an alternative would be just to show it to the player during the Stage 1 screen.
I've already decided to make hitbox visible while focusing, though it can be surely recognized even when unfocused, watch drawloops in player scripts where i've made an adjustments for it's appearance.
Power: I've never been a fan of the death = you need to collect 100 power items that UFO introduced, but that's your prerogative. The amount of shots to take down enemies in the stage was fine, but I think the boss has significantly more HP than it should (particularly given the random movement of the boss and the long delay on the Waverunner missiles). I don't think I killed a single 'spell' or 'nonspell' within the time allotted, even the during final one where the boss stands still, I remained under it the whole time and didn't kill it fast enough. I died once in the midpoint of the stage, so I may never have reached the power level expected for the first boss (though I would argue this isn't an excuse).
I've got familar with this power system in Ten Desires and found it fair. 1st stage is about collecting the precious power, and this test one was designed to make player easily collect 3 power before the boss (or even 4 with some effort). As for fighting bosses with low power - dont forget that both players (especially Waverider) have powerfull primary "weapons of last hope" wich allow to deal good ammount of damage even at low power. Waverider's Gamma Ray fires a short laser impulse on a single shot button click when player doesnt move. It deals 50 damage with total penetration. I'm even thinking about nerfing it a little cause once you can stand still in front of an enemy you can trivialize it's attack by rapid clicking

Just try it on boss and see how it works.
Gameplay: Liked what I saw. I'd adjust the boss's second nonspell such that staying perfectly still wouldn't let you dodge all the bullets. The mindfuck turrets were awesome, I can imagine some ridiculous stuff happening when the patterns get more intense and those things are around. The suicide bullets were fine too.
That nonspell is easy enough for easy mode

It will surely be more trickier on hard. Glad, you liked the turrets. They'll make a lot of fun in this game.