I'm really loving the looks of these ships. Very unique and definitely human in appearance. I can't wait to see the development of this game as it progresses, this is all looking quite good.
As for the in-game descriptions, I suppose I can give it a shot:
Frigate: A lighter ship with varying armament for reconnaissance, fast-attack strategy or support fire. Versatile and varying in ability, Frigates are certainly a critical unit in any task force.
Destroyer: A super-light ship built with incredible firepower for surprise-attack and damage-dealing. Impressive in a fight, but must rely on other units for protection to stay in the battle.
Cruiser: A midrange ship with all arrangements of armament, able to engage nearly any target. Able to suit any purpose, every forward force must have one of these.
Battleship: A heavy ship with incredible offensive abilities, the battleship is integral to making yourself a formidable force. Although able to really shift the course of a battle, the battleship is still reliant on other units to find the enemy and stay at range to have the greatest impact.