Thanks for the feedback xodarap777! This is very much a prototype and not a vertical slice, so I wouldn't consider the core loop to be done at all.
A lot of what you're talking about is stuff we've been trying to figure out from day 1. We want the game to be more city-builder-like and we're still exploring the right mechanics and systems to get the experience we imagine.
As for the game feeling puzzley. That's just a consequence of having a high difficulty level. Which is something some players really love. It's tricky to balance, but I really wanna add some different ways to play the game.
I don't think we'll do pausing during waves, but I want more customisable difficulty in some form.