Completely agree on these points.It seems there is not enough of "the place" to experience without the itineraries, though.
Activities all have limited capacity so they have to schedule them to give everyone a chance to cycle through and since it isn't a real cruise, the facility lacks a lot of the amenities people would expect for an at-your-own-pace "criuise".
The story and the character interactions are the whole deal and that's done with paid actors so you can't expect to be able to just go off on your own and stumble into an "adventure". That chance surprise encounter has to be scheduled to make sure everybody's at their markers when you walk in.
Otherwise, what is there to this experience?
You can peruse the entire ship and fully enjoy Sublight Lounge (drinks and Sabacc) between boarding and muster, just a few hours.
Yeah, there's parts you can't explore until the story unlocks them later but the locked spaces are purpose-built for the story and there's very little to them when exploring on your own. We managed to tailgate into a couple of these spaces before they unlocked for our story path and there was really no point for us to be there without the story making it relevant. We left almost immediately.
I guess if you wanted to go off-story you could play a lot of space bingo.