I'll take a look at the shop hints next time!!! I just finished playing again hehe ^>^
I want to recommend (if you continue building the game) to make flying units pass over rocks and little guys themselves. The collisions weren't really making sense with them and it made the very cute Little Koog guy or whatever (dog w/ bow :3 ) not as fun to play, but I LOVED the feature (I dont wanna spoil in comments haha)
For that above reason, it made the "my real name's John McGuy" better, which essentially was the same role as the Little Koog but worked better due to not having to have a reliable flying mechanic as much (but they also still struggled with the collisions).
Some collision issues also applied to things like Butter guys and becomes more noticeable with the red rarity guys and on, but for Butter specifically it worked due to butter being slippery lol