Thanks for the feedback! I will definitely rebalance it/change some stuff, units were actually staying at the start but at some point I have realized that buying a lot of units isn't really punishing and wanted progress to be not just perma upgrades between runs but also knowledge being an upgrade by itself. "If you know how many units you'll need for a particular wave then you can invest the rest on buildings", is what I was aiming for. But in the end as you can also tell I couldn't balance it nicely which made early game grindy and late game pretty easy, so appreciate your feedback a lot! I will definitely improve and also will consider balance part from the start next time, not as something "I can fix later".