You can get HDrums paths off of my Drums FC vids, at the very least. I could conceivably work my way backwards toward re-finding the optimal paths on Easy-Medium.
As far as Expert goes, that would be where my ability ends. The only paths you could take are the songs I have FC vids for, and anything in the latter tiers I did look at paths but didn't try to follow them much since I have no chance of FCing those songs anyways.
As far as the other instruments, that I can't help with at all, sorry.
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