Seniors can't play like a freshly-out-of-college kid who's not 30 yet. Hitting heavy loops like these kids is totally out of question, let alone running madly just to spare one point. They'll be running quite a bit slower than back in the days and they might be able to afford only one or two big shots every now and then, so they ought to pay off right away. Bearing these limitations, new options become more interesting. Everything that happens inside the court is then of primary importance.
What I have seen seniors do, most of the time, is using the net a lot. I don't know if it is what you have seen or how you live your tennis life, but as physical conditions decline, the transition game and the net game take a lot of place. There's a guy named Brent Able who's pretty good at doing this. He specifically uses the one handed backhand to ease his adjustments and improve his transition game.
Once you are well placed at the net, it's just a matter of pulling off a well-placed volley and the point is over, so getting there with ease is nice. Some seniors will highly privilege slices as an approach shot. It earns them some extra time (versus a top spin approach), it's very consistent and easy to place on the target and their opponents rarely have the hang of keeping these balls low.
It's really inside the court that your one handed backhand becomes an asset: when you are forced to adjust, to hit low skidding balls, to hit while moving forward... it's a ton easier to have a one handed backhand. With that said, it can be long and tricky to learn and, at the baseline, the two handed backhand does have an edge. You probably hit deeper balls than your peers, especially cross-court and on the return of serve and you can afford to hit from a neutral or even an open stance while the 1HBH people must keep their stance closed all the time.
If you feel like you hit a solid backhand, do not change. If you feel like it doesn't fit your game anymore, do not waste time trying to built a 1HBH out of scratch: get a good coach, even if for only one or two lessons, and learn the basics first.