Since this also seems to be the most appropriate place. I have an Aquila I ccu'd from a Blade. Should I leave it as is, or CCU to Carrack when that option opens.
Suggestions?
That is strictly going to depend on what you plan to do with your exploration ship.
I intend to use my Carrack as a command vessel when I lead fleets and use it to explore in with a group of friends. As such I chose the carrack over the aquila since its more capable in most every way (even if it is larger target and more expensive). I do intend however to buy a Aquila once game launches to use in the same manner as the Carrack for those times when a Carrack is just to much to bring.
Advantages of the Aquila is the smaller size and crew requirements while still being a very effective long range exploration ship with everything you could possibly need. Rover, Snub, dedicated sensors, extra fuel tanks, decent armament, good defences, and less cost to run when out exploring. The only down side compared to the Carrack is it can do everything the Carrack can just not quite as well.
Advantages of Carrack are more room for friends (if you have a lot of them), Upgraded rover, exploration focused snub, a supercomputer for number crunching all your sensor data, a map table, Defence focused setup (large shields with mixed turrets), and the prestige of being the biggest baddest explorer around. This comes at a cost tho. Large cost to operate, large juicy target, and if you don't have a lot of friends on when you are on you really cannot operate the ship without more cost for NPC crew.
At the end of the day its up to your wallet (we all know some wallets can't handle the cost) and since you can get both in game it really doesn't matter too much in the end which you have. Other than the few things the Carrack has the Aquila does not, the only difference in the two is bells and whistles. Gameplay wise they will be much the same and one will incur a larger cost to operate. Not to mention Aquila's in my opinion will be far more abundant and used for that very reason.