Glad the thumb ring is working out for you. Hopefully that holds up long term.
If it gives up on you, I'd say go ahead and tie on a D-loop and use a release. Could even get a retro leather buckle wrist strap made to add a little traditional flair to it if you felt too awkward about it.
Changing hands would be another option. Takes a little getting used to, but you obviously know the mechanics that go into sending arrows down range, would just need practice. I shoot either hand, different bows, different releases, but just as accurate with either.