Probably a better investment, IMHO, if you are not able to recover the shoulder strength.
My first thought - lower your current bow to 40 pounds, and dial it in, add weight to the arrow if you are worried about penetration at the lower poundage.
By the time you buy the Triax, and get the correct spined arrow for the lower poundage, and test all over a chronograph - it's going to cost a bit for that much equipment change.
Yeah, the new bows are more "efficient" aka faster, but keep in mind that the IBO speed is based off of an industry standard arrow, typically around 300 grains, and most hunting set-ups are typically pushing at - or over - 400 grains of arrow weight.
So, your actual bow speed with a hunting arrow is most likely going to be closer to 305-320 - or less - with the Triax.
I think you're going to see very little return for the investment - does WI have a minimum poundage for bow hunting?
