thief (crit chance) shadow (crit dmg) warrior (weapon power), serpent (stam regen)
Basic rule of thumb:
*damage is flat statistic.
*Crit chance value is diminishing (the more you have, the less benefits extra point gives)
*Crit damage is rising(the more you have the much better effect, BUT for c.dmg to truly shine you have to achieve certain levels of both weapon damage and crit chance)
Large percent of people in pvp use inpenetrable armor, which diminishes crit value so for PvP warrior is best one. Serpent could be good choice only on Azura if you don't have proper regen gear. And maybe, just maybe, for 100% molag kena uptime DPS (if the regen bonus is enough to make it possible)
In PvE it depends how much CP and what gear you have. Generally if you are low on CP (200<) and can't pull at least 50%+ crit take thief. If you can't pull 3k weapon damage take warrior.
If you can pull 75+% crit chance with high weapon damage (like 3,5k) Shadow will be best.
If you have big pool of CP (450+) propably (i didn't test it) divine TBS with thief and shadow or warrior and shadow, could be best.
Other mundus aren't good for stamina builds.