Well, VA's Hades has two 4096 textures, one for the hull, one for the greebles.
I intend to use one 4096 for the Colossus hull, and use normal maps for the greebles, as there's less conspicuous hull greebling here. Another 1024 map should suffice for the turrets and radar dishes. The hangar itself will be detail boxed, and use its own texture.
To answer your question, Water, size the texture as you see fit, and we'll scale it down if we need to. I personally work at twice the resolution I intend the final product to be, so I can afford to be a little sloppy and not have to be pixel-perfect or fix all my aliasing. If you're putting all the low-poly low-res fighter textures on the hangar map (and you should) you're probably looking at a 1024x2048 sized map.