Very fun game loop and love the reverse DOOM idea, I think you capture the DOOM feel great, and feels great and high-action to play. Great visuals, homage to the real thing while having your own unique plant-y style.
I will reverberate the sentiment that there is a bit of latency when buying and placing units but it is pretty manageable.
The balancing is a bit strange though, I think and it feels like both my win conditions were based on some lucky cascade configuration. I also think my second win condition was only because funglers started roaming the arena without being engaged