Also, while rules stipulate that Marriott "could" expire the account and points, in reality they don't seem to be doing that. My wife's account sat idle for virtually 10 years until we remembered her account. It was still active and all the points were still good.

So personally, if you can find an easy, no cost way to get a few points (i.e. apply for the base Marriott Signature Visa), then go ahead and give yourself some piece of mind. But if you can't find one, then given your current points amount and your limited earning potential, I would take my chances on the account not expiring.