Yeah, I'll agree. I mostly build with aesthetics in mind, but choose one or the other. Tanks, submarines, and other military machines in real life are cramped, hot, and barebones death traps. Optimized for function not comfort.This game requires either efficiency, or looks. Its a compromise. Trying to make it not a compromise just breaks things.
A good builder can work around the system anyway and leave a little deadspace for some kind of corridor or small room and spice it up with wedges and such. Those couple off free spaces left aren't going to make a huge difference anyway.