I can't imagine that there will not be other versions. The Pez dispenser is just solving the problem at hand. Eventually, I wouldn't be surprised to see cargo bay doors similar to the shuttle's.
Yeah, they'll have more versions for sure. There are two main designs that have been discussed / shown before (one where the entire nose hinges "backwards" and exposes the payload, and one that looks like the shuttle bay doors). And I think that for NASA decadal projects (i.e. JWST-like big telescopes) they could even go with a non-reusable Starship, with "regular" fairings that get dropped.
That seems likely. Best guess is the relatively small slot sized door is a cautious design while they're working out issues with re-entry heating and stresses and sacrificing ships into the ocean. Once they're very confident they have the configuration for the 'hot' side of the starship working well on re-entry (and probably after they've returned and caught a few), it could be expanded in size.
