Better player feedback for slowing time
Raising the contrast between the player+enemies+bullets vs. the background is something I've considered, and still might add some time. In the full game bullets do produce sparks when you graze past them, so that might improve the feel somewhat.
I realized that I could still interact with things even when I was facing away from them, which resulted in me accidentally interacting with a few things that I didn't mean to.
I don't entirely understand this one, the button for interacting with things does nothing else, so I'm not sure why you'd be pressing it when facing away from something and expect something else to happen. A related concern is that it's easy to talk to the same NPC again after closing out the dialogue with them. That's something I want to fix.
Better bullet colors
This is something that maybe could be improved, but it's the kind of thing where specific examples would really help me -- there are multiple backgrounds, after-all. It's been a while, but I believe I may have adjusted the colors on the bullets since the demo anyways?
Boss direction indicator toggle
Specifically removing it for masochist isn't something I'm interested in doing, because I think it's the sort of element whose inclusion allows me to ask more of the player in terms of dodging things. But I agree that just having the option to turn it off wouldn't hurt, and that's been a "Nice To Have" todo for a while. Probably something I'll do right before releasing the full game.
Shadows/better depth perception
Yeah, I agree. That's probably the biggest failing the game has in terms of visual readability I think. It's something I've tried to solve mostly through making raised ground use a different tile color, but it could still be better. Painting on shadows is definitely something I should consider, but I'm not sure if I'll have time.
Dialogue Box
This is a probably the most oddly controversial thing in the game, and I've had a lot of people say they do and don't like it. I guess it probably comes down to what one's habits are for advancing text -- I think Vacant Kingdom is set up to help people who sometimes advance through decisions without realizing it.
That being said, I do think I mostly agree with your side these days. I do want to tweak it somehow before the full game is released, probably by defaulting to the first option but delaying selection a bit.
Exiting dialogue with the back button is a good idea, but not essential probably. It's going to be one of those things that I'll do so long as I can think of a way that won't take more than a few hours to add it to everywhere appropriate in the game...
Anyways, thanks for leaving feedback. Noted about beta testing -- i'm not quite ready for that yet, but it shouldn't be too much longer.