oh my god im so sorry i just read your analysis and i have to ask; have you got any theories on striker's past? ever since s2e6 a common one has been that he was once in a relationship with a royal, and exactly like how fizzarozzie are a bright, hopeful reflection of what stoliz could be, striker's past relationship could serve to show how rotten, discriminatory or fetishistic a relationship between a low rank demon and a royal could be..... an angle i'd wholeheartedly welcome!!
I'm glad you liked my analysis, to answer your question, I'm not dedicated to any given theory about Striker's past, though there are 2 that I keep coming back to from time to time.
One is that his family was displaced from their rural home and that this directly lead to their premature deaths, the main evidence is that his family is the most likely thing for him to be referring to when talking about having things taken away, maybe he even has some slight sympathy/empathy for Stella if he was particularly close with his own mother.
The other one, which has some overlap with the first, is that one of his parents, likely his dad, is a noble and Striker being his illegitimate child lead to him abandoning Striker's mother to protect his image and publicly denouncing her if she spoke out about it, maybe even eventually having her "taken care of". I've seen an extreme version of this propose his father is Leviathan, hence why the show is taking it's time to address Envy as a ring. Some evidence is that he's literally green-eyed (a term for being jealous/envious) and his serpent features, though I don't really buy this version of the theory.
I also don't really buy the "royal ex" theory, I see where it's coming from but I just don't see it being right. There's better things to parallel stolitz with.