The ships name is Camelot, in theme of Arthurian names. Somehow, I can't imagine there being two of these in service at once.
As for phasers, cannons only would be suicidal in a world where beam technology exists. Star Destroyers didn't have them because, well, they didn't have beam guns, only beam sabers. Cannons are useless once you know you've missed, phasers can be corrected mid-fire. It's only logical it would be a mix of strips or circles and cannons, not only because of fighters, but point defense!
Anyway, as FarShot pointed out, I totally botched the hangar, so I spent all night fixing it! I love working on this ship that much. So here is the rebuilt hangar, it's huuuuuge.