This to me seems like something of a no brainer, I know it been mentioned before but how many people would like to be flying a T5 Galaxy class or T5 Intrepid? I'd wager a good deal of people, myself included, would absolutley love this idea and should be quite easy to implement as unlike new ship design these have already approved and in game. It would vary the type's of ship's we see and as they're only a skin nobody would be at a disadvantage.
Even if Cryptic didn't want to just add them to the game how about as rewards for doing various missions or even (though not preferred) through the C-store, again I'd bet more people would be willing to use their points to buy these designs than some of the new ones.
I guess we'll just have to wait and see if Cryptic take notice and look into this, I know I'll be keeping me fingers crossed (though hopefully not to long - have you ever tried playing while your fingers are crossed :p).