Matching a drive shaft to power and speed is a standard race car problem and I've seen formulas for calculating diameter and wall thickness at various lengths and speeds. ...
Those formulas (and how and why to use them) are also in the Spicer driveshaft manuals found in the driveline tech tip.
I've printed the manuals and stuck them in a notebook, handy to have and easier to use than flipping "pages" on the computer..
Grigg