Wow, I genuinely cannot believe how long you spent with this game, thank you so much! A lot of the points you make are simply related to running out of time, eg no audio, bugs etc. Probably a stupid idea to do my first ever jam over the Xmas period XD. 

I actually  learned a lot through watching. 

• First wave of static demons don't seem to work when the tutorial is off - Weird! The whole thing with the tutorials is interesting. There are booleans knocking around the tutorials so that you don't need a new one before the previous one is finished, and I guess I've  put stuff within the true conditions that shouldn't there.
• The rotation  is unintended, so I have already fixed that in dev
• I have never tried particles or dying effects. Since submitting I've realised I need to do something about kill radius, so I'm adding that. I've added an animation for demons getting damage, but the kill time is so short that you can't see it, so I'm going to try a "post death" animation. Thanks for the tip
• You mentioned that the demons are a bit out of place. Maybe a similar animation to the main cloud would be tie them in. I'm no graphic designer, so I just went to flaticon for them, and they had no better demons. I did some colour amendments in GIMP to make them stand out, but watching you play, they seem lifeless compared to the cloud, even when the second wave are converging on you.
• Rain tutorials never seem to come up - basically it starts and stops randomly, and is a secondary way to die. It uses up your water. The parameters are such that you can't really die that way right now, so I need to tweak them
• I like a game that isn't too difficult at the start, but I think  watching you play it's too easy. You lose water when you strike, and I adjusted it to be less. I think it's now not losing enough.
• You said you thought it might be an infinite game. It's not intended to be, but again, time constraints meant I didn't get to it. It's going to be a kind of comedy ending where the angel just wandered off to go shopping or something.
• It took you longer than I'd expected to spot the slider at the top. I didn't want it to intrude too much. The main reason I didn't is because the character indicates it. You mentioned that at the end, so I feel a bit  vindicated, but with the rain/death thing, you have no indication, so I'mma make it a bit bigger. 
• Similar thing with the score, but also I put the label and actual score at corners as a quick fix (time constraints again) so they don't overlap. I suppose I could do it as a single string - "Score - " & score.Round().ToString()
• So glad you enjoyed it, and found it relaxing. Relaxing was very much an aim for the game. The eye animation seemed key to that. Actually, as soon as I put the pupil animation in, I was in love with the little guy. By the time he was blinking and squishing, I was 100% sold.

Definitely needed more playtesting! I accepted a couple of bugs so I could make the game feel a bit more complete, and I think that was the right decision.

I have a couple of other games on games.4godsache.co.uk, including one I'd eventually like to sell when it's complete (Quad Pong - like pong but completely insane and not relaxing at all). If you ever get any time, I'd love to hear your comments on them.