My best guess would be to leave it alone, that way at least any moisture that may get trapped in the belly pan would have some where to at least attempt to evaporate too. BTW I am at the same point with my Sovereign
Just got done pulling the scuffed cracke parquet that some PO had put in, along with about 50# of sand that was trapped in the cracks
I don'd plan on any sealant of any kind, just a light sanding to smooth out some rough areas, and some wood epoxy mix in two small areas where I have some surface rot.
Aaron