Thanks a lot for the feedback!
1. I agree the upgrades aren't very balanced at the moment.
2. Yeah the game is quite repetitive, there's actually only 6 map types, so the game just picks randomly between them, we plan on adding a lot of map variation.
3. Yeah I'm not quite sure why it happens, but it only happens if you die on the first section of the game, I'm gonna rewrite all the code for restarting the game, so I hope this bug will be fixed.
Thank you very much for the feedback and for playing! Knowing that you played the game for quite some time makes us really happy! Most people won't play it for long enough to buy upgrades. So thank you very very much <3