Thanks for taking some much interest in this JG. Yes, please email me your response I think it will be very helpful. There is definitely something very deep here for me, even reading your response had in tears and I'm typing through tears.
There is definitely a connection in my head between polyamory and God not co-habiting comfortably. It isn't to do with sin, or historical rules but more that it seems to be one of what I'll call "The big Suggstions" that most people who live their lives from a Christian platform adhere to. Other "Big Suggestions" are things like, "As you sow shall you reap"; the whole thing about idols and money; "Be as little children" etc. I believe in these premises because I have observed them work out well more often than not. I've noticed that when I apply them to my life it goes much better. Remember this is purely my philosophy.
As I've said I'm also open to the possibility that I am just battling my own ego. I'm using the principles of AA to deal with it, which is handing over my will to a power greater than myself. This is another "Big Suggestion" that I have seen works out best for me. I'm trying not to project out too far and just live each day to the best of my ability and leave the rest up to God. This seems to be working well.
"Are there more issues than just polyamory involved? What about security, companionship, and simplicity? Are they missing too?" - No, I feel very secure in my relationship, we live simply and are best, best friends. My problems are around depth of relationship and feeling. There is something disturbing for me in being totally invested emotionally when my partner is not because he also loves someone else.