I started playing in the 1970's with a 1-hander. I switched to a 2-hander last year. It is finally as reliable as the 1-hander and still improving. My advice is to use the racquet that works best for your FH and serve and is serviceable for your BH.
The best thing you can do to help your arm if you move to a 1HBH is to play a 12 oz. + racquet. If you don't want to move up to this I don't see a need for you to change racquets. For my 1-hander I prefer a very flexible 18x20 in the low to mid 12 oz. I really like the PT630 and also the Babolat Pure Storm LTD. I got much better results playing with an AeroPro (with some lead) since it improved my FH so much. Not the feel I like best for the 1HBH but I play a spin based game and the results are like night and day.