Here's the best I could do. Aiming for the top grade was a nice little challenge, although the amount of movement I had to do near the end got annoying.
I don't think there's much that can be done beyond this - I was pretty careless in some areas but every optimization I ignored except for the 25k enemies (I'm not sure whether this is possible while getting all the x2 elixirs, though I believe it to be. I didn't track my pickax uses.) would barely affect the end result. Feel free to prove me wrong though.
