I did enjoy it but I only maybe put 10 hours into it or so. I think it tried to be more than L4D with all the perks/cards or whatever but IMO people just want a simple replayable zombie survival game you can spontaneously jump in and out of with some friends
Not saying you're wrong but I do feel like there's still so much of the universe to explore, even if the main arc is complete. I would love to learn more about Rapture