We were on an Eastern twice and had one of each. We were portside on Deck 9, then Starboard on deck 8.
I don't remember doors (as in guest room doors) on the inside of starboard side deck 9. In fact, all the inside rooms seem to open to middle walkways.
I can tell you that the laundry is forward deck 9 on the starboard side. You don't say which end of the ship you're looking at, but if that's a factor for you, maybe starboard is better?
We liked the views on the Port side, but it was away from all of our ports, except CC. On
Castaway Cay, you could be on the balcony and watching the land team waving goodbye to you. You could also be on the verandah and watching people come and go from the ship. It was the only port where this was so.
On the Starboard (aft) side, we were able to (illegally) watch the fireworks from our deck (I didn't, DH did, the renegade!) We also were able to people watch in Port Canaveral and we had the view of Fishlips, et al. on the way out of port. (Portside could see NASA, though) We were also able to people watch in our other two ports, but our view on Castaway Cay was of the beach, not the port. Many people like that and it was nice to see the last stragglers when we were back on the ship already. More accurately, we were jealous that the last stragglers weren't being rushed back to the ship, because we would have stayed longer, if we'd known it was possible.
Other than that, there really was no difference in which side you were on. We enjoyed both. If given a choice, I guess I'd go Starboard again, but if Portside is all that's left, I'll still take it.