I haven't seen a first person survivor game yet so props on that idea. I think this could have gone wrong but the map kinda makes it work.
I also really like that there is some actual aiming involved in the beginning of the run. Generally the beginning was the most fun because you actually have to look out for enemies trying to swarm you. Later on when you have all the upgrades it becomes a little repetitive but I guess that is just an inherent problem I have with this type of game.
I found most of the cards to be not that impactful except for the death card.
Generally this was quite fun honestly. I got all the upgrades in my second run when I knew what the colored upgrades meant and got to level 110 at the end.
Fantastic game. Keep it up.