Welcome to the forum Firemedic.
Looking at your to do list, I would recommend doing all the least invasive things first without replacing the belt, etc., and go ahead and get it cleaned up as much as possible, then just print.
For all you know, the belt may have a lot of life left in it. I usually take a "if it ain't broke, don't fix it" position before tearing into the printer, unless of course, it's a total tear down and rebuild.
Running it would give you time to suss out how it's working and see if there are additional issues needing attention.
Mark