I like the art here - clean and simple. The designs I don't know about - they *look* nice, but also much too close to the original inspiration. Considering what a difference of twenty years makes, it's very strange to think that ships from a hundred years earlier would look virtually identical to those from the modern era.
The Gotha is lovely, though, like a classic space rocket, although given its origins I guess the aerodynamics are questionable (isn't it originally a surface-to-space bomber?) I'd give it much longer wings, like a WWI bomber (which might also help accentuate the age of the ship).