First off I have not yet been testing seated EUC riding. That said from what I gather it is not at all like sitting on a mc (not ridden that either).
I started myself due to rheumatic conditions in mt knee, lower back and shoulders/neck area. But it spread further. I were so bad I couldn't stand on one leg to wear a sock or put on a shoe. But learning to ride was hard but after 5-6 training sessions of 10-15 min I got the basics. Now 1 and 3/4 years later I have like 2300 miles all together one 4 different wheels.
If you pick up EUC riding, I think you will find a new level of transportation freedom, but you need to accept the risk too, as accidents can happen. And if they do, you might not have much to say in what happens. Some of the biggest injuries posted about happened at standstill or very low speed as people got caught out by surprise.
I think in a poll made some time ago we saw average age is about yours so that is not an issue. I think you will find the ridding is fairly gentle as long you don't go fast. mainly since you stand on both legs and in somewhat static pose. I can't walk on tilted terrain. But I can ride my EUC both up and downhill without an issue. Once you get the basic covered, you find it is very similar to skiing, but not limited by going from up to down, but going anyway you choose between A to B.
I got a lot better very fast (I am in less pain, and can move a lot more now), but that is not the same for everyone. Everyone at my work said that it was an crazy idea to do, but these days all of them are happy for my achievement and how it changed me.
I can only say riding seated you are in a lower position but also locked in and much harder to react for an accident or act it you hit a pot hole. I would personally not recommend this.
I hope this was helpful, despite I can't give a yes/no answer to you.
Note: I slipped my wheel on Friday due to winter season here, icy patch on pedestrian passing, while braking and turning. I hit my elbow but since I were fully geared up I only got a slight bruise and a tiny scrape mark.