As a whole, I agree with @Antonio, LFs need to be more like a scout force, or utility pursuit force to CD runaways.
To balance things like the liberator, remove some of its guns (as Arrow and Hayabusa have 2 and 3 guns respectively), you can drop 1 gun (or 2) off a liberator and give it something else.
Or, upscale it slightly (15% maybe or something similar).
All in all, DPS doesn't make much sense for a LF, since its core should be that much smaller and weaker than a VHF. Instead, you can make them have some sort of Pulses that eat at the powercores of larger ships, or maybe have them be able to use cloaks more effectively for scouting reasons.
As for repair ships, I agree - we need more of them. But turning every LF into a repair ship isn't good imho. But a big yes for more utility roles for LF's. Let them do more harassment instead of damage and have them be useful in combinations with other ships!
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