I've been having a problem with my right hand. Not so much from computer work, probably due to age... Definitely made worse by snowblower overuse a couple years ago, but that's another story...
At any rate, I too felt like I needed to move to thicker sticks, and I even tried some maple ones for weight savings. Seemed to help, but then a little numbness would set in. I try to be aware of technique, and I know I'm not gripping too tight. (I can see the label slowly spin as I play.) I like a stick with a diameter around .550 - .555.
Part of why I thought thicker sticks were the way to go was because I always keep a set of Regal Tip 5A's around (.580). They were more or less my first stick, so I had them for nostalgia as much as anything. I did notice my hands always felt better when I used them.
Recently, I've noticed I can use any size stick as long as they are Regal Tip - I believe it's the lacquer. (I'm also going to experiment with Vic Firth Doubleglaze.)
It might be worth a try.