I realize you're venting, and I understand that. However as others have stated, many of the items on your list should have been observed by a detailed inspection by someone, such as yourself as a former owner of four coaches.
The size of the compartment for your satellite receiver is the one that mystifies me as that should have been very obvious. I have a large compartment on the PS that is more than adequate to accommdodate my receiver and HTS.
Regarding item #7-Remotes. Mine came with the same Panasonic system, but I have upgraded all the TVs to different models, so it's been a while. However when I had the all Panasonic system I believe they had a mode selection called EZ Sync (or something like that), that would do just what you're describing. You need to read the manual and go into the on-screen menu selctions to turn that feature off. Then each TV will work independently.
Sounds like you might have a hydraulic leak on your DS jacks, but for the most part, as others have stated, you have a four year old coach just needs some simple repairs.