I don't know the platform and would -guess- that this won't actually help, but it's sufficiently fascinating I thought I'd share anyway: https://trout.me.uk/lisp/vlist.pdf (roughly "stitching together efficient cons lists out of arrays")
(and /lisp/ has an index if you want to see the other random lisp-related stuff I've collected copies of so I can find it again later)
We just roughly doubled the speed by changing one line of code, that means there's plenty more fun before it gets really tricky.
My issue isn't really profiling, its not knowing enough about the platform to do anything constructive with the hot spots.