StarTrek pretty much all the UN-UNSA ships. The destroyer, the cruiser, the corvette, the carrier... Destroyer and the UN 2190 exploratory ship are probably my two favourite ones. Awesome level of detail and very realistic sort of feel to them which I don't get from any other ship designs I've seen. The two you've posted look a little more generic (though the Battleship is slightly better). Maybe it's the empty space that's left due to the size of the ships? Not sure - this is my personal opinion anyway.