What purpose would a frigate carrier serve, except being easy punching bag?
Throw the high-tech pack a bone! It only has three ships: Wolf, Shrike, and Apogee. Low-tech and midline have a bunch of useful ships and one or two carriers. High-tech pack is anemic.
With the skills rework, granularity to fit within the six or whatever bays for maximum bonus from skills (bonuses get smaller after some limit break). Player can have a cruiser, destroyer, and something with a single bay (that is not Gemini, Converted Hangar, or custom built-in). Granted, it could be like Logistics where more ships was always better than unused efficiency bonus (and sometimes worth taking CR penalties for exceeding Logisitcs).
Short CR is a problem for all small ships. It is a reason why most frigates become obsolete shortly after a new game.
For slow and defenseless, it cannot be worse than Shepherd, and Shepherd is one of the better ships in combat early in the game. Of course, if the new frigate carrier is stupidly rare like most high-tech warships, then early-game play would probably be irrelevant.