Honestly I just think the boarding part DoT should ignore shields/shield mitigation.
A). it doesn't make sense- once the boarding party is on board what the hell do the shields do to stop them from causing havoc?
B ). This would make the ability more reliable. Accounting for armor, drop the dot on a ship with under ~275 health or lower an guarantee the capture provided no healing comes into play.
I'm a little apprehensive about extending the effects to multiple targets as that opens up the possibility of this normal ability having a larger impact on a battle then an ultimate ability(dominate), which I don't think should be the case even with the loss of speed & reliability. I'd rather buff it by increasing the reliability of capturing a single target.
Moreover buffing the reliability of stealing a single target also makes for an ability with more tactical decision-making behind it(since you have more of a say in exactly what sort of ship you're stealing rather then "whichever ship in this cluster dies first").
All that said I do definitely agree the Corsev needs some love.