...One fly in the ointment; the basement location is at the opposite end of the house from the elec service so I think my grounding option would have to be a rod in the ground on the shack end of the house.
Not a problem at all. Set up a ground rod or network and connect the ground rods together with a number 6 cable. That will keep them all at the same potential and may even improve your station performance. If you just run a ground cable to the other end of the house, it would be just like running a ground cable down from the second floor. The idea is to keep the ground cable run as short as possible. Good luck and 73!