I think no matter what your ship type is, when you level up and go looking for a new ship the ship vendors should give you the option to upgrade your current ship to the newer ship stats, the gold cost to do so would be the same as buying the higher level ship. New equipment would then be added to the ship parts vendors that would give comparable stats at the same prices for each ship type as the equipment for the newest ships keeping the gold costs relatively the same for all players. Ship types could also be given their individual boosts, such as some might be a bit faster than others based upon type, some more powerful, some more better at turns, and their attack types and the like can be made different but comparable (in essense all ship types would be different than each other but comparable in playability and strength the same as all character classes are roughly the same in strength but each being a bit different than the other).

I agree, and I've had hope for this ever since beta. Many people have a certain style of ship they prefer and this would allow them to maintain that style as long as they want through the game.