For PVE DPS, the answer is almost universally thief or theif+shadow with TBS. There are a few super high crit builds where shadow alone probably becomes viable.
Fore PVP I typically run Serpent or Attronach for regen depending on the toon.
Looking at the 2, 3, and 4 set bonuses which are relatively balanced in scale then looking at the scale comparison with the mundus stones and it becomes blatantly obvious that you get much more from Thief or Shadow.
These are all roughly equivalent for DPS purposes(although given a particular build one can be significantly better than another):
688 Crit, which translates roughly to 3%.
~
967 Stam/Mag
~
129 Weapon/Spell damage.
Where these have the obvious discrepancy when in comparison:
Thief - 16.775% Crit.
Shadow - 18.3% crit damage.
Mage or Tower - 1952 Magicka or Stamina
Warrior or Apprentice - 213 Weapon or Spell Damage.
First look at Mage or Tower, in comparison to the 2, 3, and 4 set bonuses the Mage or Tower are essentially 201% or double the value of a single 2, 3, or 4 set bonus.
Second consider the Warrior or Apprentice, in comparison the Warrior or Apprentice are 165% of the value of a 2, 3, or 4 set bonus.
Third note that the 16.775% from Thief is more than 550% of the value of a 2, 3, or 4 set bonus. Meaning you are gaining significantly more stat value from this mundus compared to the other two.
Finally we come to the Shadow which provides a stat bonus that is unavailable through 2, 3, or 4 set bonus' and is only available through certain skills or 5 set bonus'.
As far as recovery, it is not truly a DPS stat but regardless the discrepancy still exists it comes closer with 248% but is still way behind Thief at 559% and Shadows unique bonus.
In PVP this is a different story because of the impenetrable armor trait which largely reduces the value of Crit and Crit Damage, although not eliminating them. In PVP your particular build will require for more customization based on your approach to PVP itself.
However in PVE for DPS purposes if you are not using either the Thief or the Shadow you are giving up massive stat value that you cannot make up for elsewhere.
Legendary Archer of Valenwood
Bosmer Dragon Knight Archer. XBox One. (Flawless Conqueror Bow/Bow)
Bosmer Nightblade Archer. Xbox One. (Flawless Conqueror Bow/Bow)
Bosmer Sorcerer Archer. Xbox One. (Flawless Conqueror Bow/Bow)
Bosmer Warden Archer. Xbox One. (Flawless Conqueror Bow/Bow)