After struggling for a while on Chloe's Ultimate badge, I've noted a couple things:
Firstly, invisible enemies are very tough, and having enemy patterns randomly have a chance to be camo or not makes the difficulty feel very RNG, to me at least. Since the camo makes enemies significantly harder than their normal versions, I feel like making camo only show up on specific, easier enemy patterns, or just give camo enemies their own easier patterns, would feel more fair. The main thing about camo, for me at least, is that you can't see when a shooting enemy is about to shoot. Maybe having the blue glow appear through invisibility would make it more fair?
Secondly, I noticed that the Bomb weapon type powerup almost feels weaker than the base shot, and definitely weaker than the other powerups. Since it fires slower than the normal shot, you end up not being able to hit all the enemies in a pattern like you would be able to with basic bullets, since the scatter isn't super reliable at taking out enemies. And it's not even good at taking out clothing, either. So, I often find myself skipping out on it when I see it, making the powerups feel more RNG than they should.
Thirdly, I think it would be a good idea if there was some sort of warning for enemies coming in from off-screen, like a flashing red light coming from where they're going to spawn. I've died a surprising amount of times from some enemies popping up beneath or to the side of me.
And finally, I still think it'd be a good idea to implement some sort of "quick-retry" mode, for if you're going for the Ultimate/Dauntless badge.
Oh, and also, I think the camera movement for Chloe is pretty wack. I get that it has to be kinda weird because of the "stockings are underwear" thing, but you barely get enough time to fully break her shoes (at least, I assume they're shoes, and not socks worn over stockings) before the camera pans away the first time, and the only other time you get to shoot the shoes off is during the Final Wave, where if you didn't have the shoes shot off before it, you're basically guaranteed not to be able to shoot off the stocking beneath, due to limited time and all the enemies attacking you. At least for the left stocking, since you start at the shoe for the right one. But it'll still be very hard. Also, you get two passes at the head, even though it's pretty easy to shoot off the head ornament the first time around.
Generally, I get the feeling that Chloe is supposed to be a notably harder mission, but the fact that she has 3 pieces of underwear with 3 break points each, as opposed to other girls who usually have 2 pieces of underwear with two break points each, makes her MUCH harder. I don't know if you can do this, but tweaking her Final Wave somehow, either to make it less compact (less enemies but longer) or simply less enemies, would make the difficulty curve between her and the other girls a lot smoother. Unless, there's something I'm missing, in which case, do point it out.