Brettanomyces Dex does not affect crit rating. Dex only helps you to maintain channeling, which can assist you from getting interrupted occasionally but you dont want to be hit anyways.
With the current items in the game, you want to just stack INT and then if an item has STA / DEX then great. But thats really it. You do not have the HP to sustain getting hit, even by a pack of 4 greens mobs at level 60.
INT > DEX > STA > AGI > whatever else your gear gives you.
People talking about carrying things...you don't need to. You're a wizard, Harry. You go off to the side, bind yourself to a reasonably safe spot, and then portal back to town, and then come back. You will be back in minutes if you do it right. Wizard does not care about str for holding items. Leave all those rusty weapons on the ground, the copper is heavy enough.