The black hole physics mechanics do put an interesting layer of gameplay on top of the usual top down shooting. I did notice however that you can get hurt by your own shots and black hole(!), which ended a few of my runs.
Hi Crow! Thanks again for the advice earlier. I'm glad you enjoyed it. The self-hurt is intentional, but I can see now that we should make it clearer (if only we had more time). That's my masochism sneaking into my work. Thanks again for taking the time!