welcome to the club.
My story is not half as interesting as yours. But gaining weight, losing experience during a longer period of absence from Aikido is something we share
I understand it is a pity, coming back to the States, not finding a dojo with the right style and inferior instuctions. Maybe you might have realized, that no aikido was not the best solution to avoid that "not as good as wished" aikido. Holding a second kyu and lots of ideas, if you had stayed, you probably would have your own dojo now.
Well, not necessarily, but even if you could havebrought in some ideas to the next dojo you can go to, it is your contribution to a better world
. Now you have plenty of ideas and not the possiblity to show how they work, as your body has to regain abilities. (Sorry, sometimes I do not know if I am talking abiout you or me)
About your ukemi: unless you really got a handicap, try to improve it slowly but steadily. Even if you might not get back to where you've been 15 years ago, ukemi is one thing you can always need in "real life" situations. Well, here I am talking about bike accidents and black ice.