o look here is a great set of end game gear that is totally achievable for the
slightly sick/non totally sick and it is in no way close to 255
https://wiki.project1999.com/Magelo_Blue:Pons
I seriously think it would be difficult to sacrafice all your other stats for 255 cha and still hit it without some serious luck or time put into raiding, but even if I was wrong and you could, when mez takes 7% of your mana pool at level 60 then thats a problem that STA or STR aint going to fix.
Not that 50 extra mana will either but you know, its still better than those 12 extra hit points or that copper/silver you dont have to delete /shrug