Purely in terms of potential damage, am I better off taking Elven Accuracy, or Mobile, as a first feat at Level 4?
- The option to disengage after making melee attacks is crucial to this question; thus the Mobile feat makes two weapon fighting viable (thanks to the free disengage after melee attacks), whereas Elven Accuracy does not (as disengage would use the bonus action instead of the offhand attack).
- The playstyle is a skirmishing melee rogue/striker, as opposed to ranged, to better complement other party member's abilities (eg. Battlemaster shoving prone, et Al.).
I am playing a Level 3 Rogue, and will soon need to select my first feat at Level 4. Currently, this Rogue has 17 DEX, and the Soul Knife subclass. Using his Soul Blades means he can currently dual wield effectively (without the feat), giving +5 to hit, and a potential damage of: 1d6+3 (main hand, action), and 1d4+3 (offhand, bonus action). Sneak attack is currently 2d6, and remains the same for level 4.
I've attempted several different ways to calculate this, but haven't arrived at a conclusive answer. Any help would be most appreciated.
EDIT FOR CLARITY ON EACH FEAT:
The Mobile feat offers no additional bonuses to hit or damage beyond those listed in the Background section above. It provides extra damage by facilitating the offhand attack through the free disengage. Additionally, the base chance to crit (5%) is doubled with two attack rolls (10%), and quadrupled with advantage (20%).
The Elven Accuracy feat provides only one attack, as the bonus action must instead be used to disengage, as specified in the original conditions above. It does however provide a +1 bonus to DEX, taking this Rogues DEX from 17 to 18, with all the additional damage/hit bonuses that implies. Additionally, Elven Accuracy gives a single d20 reroll on attack, but only if the attack is made with advantage. Without advantage, Elven Accuracy still provides the improved +1 DEX hit/damage bonuses on a single attack, with the standard base crit chance (5%). With advantage however, the hit chance improves with the third D20, while also tripling the base crit chance (15%).