If your Doctor thinks you're sufficiently fit (e.g. he's willing to sign you off as fit to drive a car) then there's no reason why you couldn't progress further with your gliding. I'd suggest that civilian gliding is somewhat different from the ATC variety - it's not all up, round and down circuit bashing - we do cross-country flying, racing and aerobatics. Check out the BGA site (
www.gliding.co.uk) and find yourself a good local club.
Gliding's as much fun as power flying, only harder.