Thank you for playing! I had so much fun making the SFX too, almost woke up my neighbors with weird shouting in the middle of the night, before I realized what hour it was and continued the next day haha..
Yeah I feel you, didn't really have time to tweak the upgrade-values and it gets bigger too little per-upgrade. I kinda fixed this issue by making the minions able to gather exp for you. Now it's pretty fun to make them run around with the flag to gather any clumps of exp. Of course can't upload the jam entry but we'll make another upload at some point and/or we'll make this into a full game eventually.