For now I'm thinking a mix of both: very fast hit-and-run tactics at knife-fighter range, with low staying power.
Their weapons will be more damaging than vanilla, but have half the range, and the ships have fewer mounts so vanilla weapons will be less effective. They will have average frontal shields, high flux reserve but weak armor and no flux dissipation (with fast venting to compensate). Their turrets will have wide arcs and a strong focus point, but there will always be a spot less covered by big guns.
In addition I'm thinking to give them almost no CR deployment cost, but a constant degradation from the start witch imo is much more logical than a flat rate: when you obliterate 3 freighters in 20sec, you won't loose half of the CR of your flagship and hundreds of supplies. On the other hand, prolonged fights could make your ship you malfunction.... If only I can get rid of the alarm every few seconds!
This is only a idea right now, the untrustworthy AI could wreck it, or it could create too much micromanagement, or even could be not that fun to fly those ships... Anyway, we'll probably know soon enough.