Nice game, idk if you're still working on it, but if you are I hope I can provide some feedback.
- I think melee weapons could be improved to be a bit more powerful As it is, they are generally less desirable to guns in every way, which may be fine, but it just causes them to seem useless. One way they could be improved if you don't want to buff the damage is to perhaps make them more effective at destroying walls. They already do this somewhat well, but making it even stronger would encourage players to actually make use of this as a feature.
- When enough enemies are killed, more seem to respawn immediately. To me at least, this diminishes the reward of killing enemies. When I kill an enemy, I like to think "that's one less enemy" knowing that I've progressed towards eliminating the threat. As it is, killing them feels less like killing them and more like teleporting them around, making the player's actions feel less consequential. Perhaps using waves, or a continual flow of enemies, or even removing enemy respawn as a mechanic could improve this.
Overall it's a fun experience, nice work!