I had a lot of fun playing Neon Rain! one small thing that took some getting used to was the ui to place blocks down from different categories. This is probably due to my inability to read tutorials. but once I understood how to navigate it was fairly intuitive.
The power generators were also not super intuitive. I didn't realize where i was getting the power from at first because they were spawned in automatically.
As other people mentioned, it seems more affective to just place blocks instead of placing guns. I think one way to combat this is to make the player only place blocks next to existing ones, and give the towers health that gets taken away when hit so they aren't destroyed immediately.
Lastly, I think there could be a little more variation in the level design. they don't really stand out apart from each and just seem more like the same. I think if there were some more enemy types introduced, for example a regenerating one that recovers hp if you dont kill it fast enough.
that being said, the constant pressure of defending my income generators, as well as the core lead to a very fun challenge of balancing many things at once.
I love the retro sounds and the neon artsyle. You did a wonderful job with this game!