The more repetitive the movement, the worse the pain will become. Maybe you can incorporate some new movements in your massage tx such as using heated stones or something, so there is not the constant pressure on your wrists and fingers?

You might be having tendonitis caused by the RA RD. The channel your tendons run in get enflamed and can cause you the pain.
I had it first in the 1990's in my thumbs from counting money all day long. I was a bank teller at the time and it was before my bank bought the money counting machines.

So long story short, yes repetition will hurt your hands due to RA.

I have yet to fine solid relief from pain

I think so because i was a cashier and developed carpal tunnel in both wrists. Trigger fingers n both hands. Ive had several sugeries and after all that i went back to work as a beautician and now i have Ra its affected my hands ,feet, elbows on both sides. Im like a toddler 1st thing in the am trying to walk after getting out of bed.

I couldn't do a deli job because the repetition of using a slicer aggravated my wrist and shoulder. I could not imagine being a massage therapist because my hands are sensitive so would hurt too much. I give some massages but after a bit my hands hurt. It's not that the repetition causes the pain solely but the RA makes joints inflammed sooner especially if it's not well controlled that's why we need to protect our joints. Everyone's different though so you need to listen to your body.