Thanks for taking the time to leave so much feedback, you bring up things that I haven't seen from anyone else yet.
The minimap stands out to me, you've definitely got a point about how vague it is, maybe adding a skull to the spot where the rift is would communicate better that's the spot where bad guys are coming from.
I'm glad you liked our game, we poured a lot attention into filling the interactions with as many small details as possible!
The coolest thing about this game to develop, is that even though I programmed every bullets behaviour I still don't know the best combos, and I still get surprised every now and then when I fat finger a new bullet and go "woah what was that".