SSBN?
Its alot bigger than the other subs (LA, presumably) and it has the island all the way forward, to accomodate the silo's in the rear. Just a guess, though.
I don't know about you, but I dont know many jets or semi's that can transform. Who's to say What they should sound/look like? It's a movie. A movie about machines from space.
Why IS Kaworu there? The only thing that I can think of is that they are going to show him working with SELEE (sp) for the dummy plug system for the production EVA's..