Congratulations on all the lifestyle changes, weight loss and getting off the diabetes meds! And welcome to TE!

You can do a ton of research on bikes but at the end of the day you need to get out there and do some test rides. There are some fit calculators on line if you want to just get an idea of what might fit you, especially if you are going the route of buying used. You just plug in your numbers and they'll come out with suggestions, and then you can go onto Craigslist and look for bikes with similar measurements.

Have fun!