I have also purchased PACX and I am aware that it is still an early access product. So far, I can't say it makes any significant immersive experience, because the only thing that seems to matter is whether the flight is on time, or delayed. There are much more factors than that in real life. I guess some of my suggestions are maybe already in the pipeline, in such case I would like to get a confirmation from the developers, otherwise I would also like their opinion about these:
Announcements. When we select to do an action like inform the passengers about a delay, or ask the cabin crew about boarding status, there should be an audible message. Currently there is nothing heard in the cabin.
Announcements. There should more announcements. For example before landing, after landing to welcome them to the new destination, etc.
Flight behavior. So far I dont think passengers respond to how we fly the aircraft. If after takeoff we climb with an extreme pitch up or the landing was too rough, or if there are maneuves or dives, the passengers don't seem to care.
Taxi behavior. Same for taxi there should be some limits on how fast we can taxi or make turns or brake. Things that can worry passengers.
Meal service. It would be nice to be able to plan the meal service timing.
Cabin Temperature. It would be nice that passengers react to cabin temperature. I know that's maybe not possible for all add-ons, but for sure the advanced airliners available on the market have cabin temperature control that depends on outside temperature and bleed air selection. As PACX is about caring for your passengers, cabin temperature can't be left out, as its a very important parameter.
I would like to know the developer's view on these points.