I was on the same boat as you a year ago. Or maybe a little ahead since I was using the trackball.
I had no luck with the game mice. Couldn't get them to work properly.
Eventually I got a Wacom tablet...and I LOVE it!!!!
My wrist doesn't hurt anymore and I am super fast
The only downside is the size. It takes a lot of space and doesn't leave much room for the keyboard.
Right now the tablet is in front of me, and the keyboard in behind it. This brings a lot of strain on my left shoulder since my arm is very extended...
I tried putting the wacom and the keyboard side by side but I ended up having both arms ridiculously extended left and right.
But still, i don't think I'd go back to anything mouse-related. My cursor travels so much on my 2 screens that using a trackball or moving a "stick" would be too much for one thumb and eventually it wouldn't be comfortable.
It also depends how old you are... I'm not young anymore.... Some late 20s coworkers have no problem using a regular mouse all day... like they have no issues doing crazy things I can't do anymore :-)