I had one of those plastic hoods that were made to look like the metal Hasselblad hoods. It was actually a nice hood. No, it won't hold up to the knocking around of a metal one, but I banged mine several times on door frames, gates and such and it held up fine. You should have no problems attaching the hood. I have no experience w/ the other lenses you mentioned, but if they all take the same adapter, that should work.
I got a lot of stares when I went out w/ that camera on a strap. I think that people assumed it was a video camera by the looks of it. When that shutter fired, I'm not sure what they thought. It sounded awfully loud to me too until I bought a Bronica S. Beautiful camera, seemed much bigger than the 'blad, shutter sounded like a gun firing. W/o a doubt, the loudest shutter I ever heard on a camera.