Thanks for the analysis! Doki and Mint's dynamic is something we definitely wanted to make a part of our game. We talked a bit early on about whether or not it would be appropriate to feature Mint so prominently, but in the end we checked with the jam organizers and got the okay.
We actually do have alternate mappings for aiming and firing! It was originally undocumented, but we've updated the game page to include them. It's Q to aim, and F / Space to fire. I worked on a laptop for most of the jam, so I definitely understand the awkwardness on a trackpad!