I think there are some interesting ideas here, that help you stick out from similar types of games that I think are pretty cool. I personally haven't seen many of the Survivor-types focus on protecting NPCs, so I think that's a pretty interesting angle to explore. Unfortunately, I would prefer you leaned into it a bit more. As it stands now, you can complete the game both without firing a single time and without even seeing any of the NPCs you're supposed to be protecting by just rushing each of the book spawn locations. As much as people dislike escort missions, I think it'd be really interesting if the NPCs were in actual danger that we'd have to handle (it doesn't have to be getting attacked specifically, but something that makes us need to interact with them). Also, the collision with the rocks was kind of annoying. I didn't have an issue with obstacles on the map, but they were pretty small, so when things got hectic it was hard to tell when I was about to run into one.
Saw that this was your first completed game, so congratulations on that! Looking forward to your next work!