In regards to point 2 - yes I believe I have very similar triggers. I take taurine which seems to help a lot with Glutamate as does b6. (converts to GABA?). High Histamine is a problem also but is unlikely to stimulate me as much as other triggers (usually Sea Salt /water / vit C / b6 does the trick).
Point 3 - I believe the Science behind high copper and simultaneously high histamine is due to copper biounavailability (seen in copper toxicity) that then cannot counter the histamine.
Interestingly the last 3 nights I have slept well with hardly a supplement taken (not an active decision it just worked that way due to circumstances). Prior to this I hadnt fallen asleep naturally before 12pm for approx 3 months. In fact in recent years it is rare for me to fall asleep without supplements.
Why? Well Ive moved house. Meant to be stressful huh? well I have slept like a dream Oh and had a high histamine Indian meal with alcohol (also high hist) the one night! This is the thing - there are so many factors involved that you cannot always focus on one thing. And many times I can have a bad diet (copper,hist), coffee and sleep fine. Stress??
I believe my previous living arrangements - cooped up in a small flat, living alone (too much time to think and not enough space to wonder) plus having a large tv screen in my bedroom could have been a big link here in me playing sleep detective. Now I live in a bigger, spacious house with a sibling and my bedroom is only for sleeping (well unless my girlfriend is round lol)!
Its early days but for me living arrrangments could play a part. i also noticed anxiety creeping more and more into my life when I was in the small flat. I attributed this to copper, histamine etc but I do believe that my instinct had told me it (the flat) wasnt right for me yet I ignored it (repressed) it - hence anxiety! (there is more to it than that Im sure but some insight is good)