I'm always wondering why people says theres no need for fighter runways. If that was the case, explain why theres two in a battlestars, and why in the serie they often crash land for meters in them, and also get launched from them?
same purpose with the unity. This is not a mere battleship that store a few fighters, this is an immense carrier made to rapidly scramble fighters, as many as possible, as fast as it can.
As to boat like design, refer to Liberty design itself.