The Jeep carriers were unsung, thought your description of them as being 'fast' is a bit misplaced. The Jeeps were quick conversions of merchant ships and most of them could not make 20kts. I don't believe the Hellcat was deployed on the Jeep carriers. The Navy wanted all of them it could get to defend the big fleet carriers. That being said, the role of the jeep carriers were huge. Even with the Lib, Cat, and Sunderland on the job, there was still a hole in the aircover until the jeeps came along.