It all depends on your personal preference. There is no "mandatory" spec.

I went full STR (also while leveling) + STR accessories. My HP is more than enough to tank t13. I don't see how 600ish HP more would make me survive better. I chose ~600 HP less for way better snap aggro and ~150 DPS more. Granted that in the current state of the game, you will most likely succesfully meet DPS checks since gearing up goes rather quickly.

My advice would be to go VIT and switch to STR when you're comfortable with encounters. Inner beast will be your best friend and it's amazing both mitigation and dps wise. You can always swap back if you don't like it.