Well, that was very long winded! But I found the last part very intriguing, and re-read it several times. It was a very perceptive diagnosis of all the problems our heroes will be facing, even if the unlikely happens and they do end up together. There's been so much pain and hurt dealt by both sides, both Jazz and Soundwave the individuals and by their respective factions. If Soundwave tries to stay with Jazz, he'll also find himself facing the entire surviving Autobot army, who are not disposed to look kindly upon a top Decepticon officer just now. And that's not even counting what Soundwave will have to deal with from any surviving Decepticons. Plus there's all the friction developed between Jazz and his own faction.

That's not even half the problems, as you well know, just the starting set. So yes, there is no HEA here, there is only the Best They Could Manage, which may or may not be right but what else can one do? I will continue to work toward the ending that I want, bearing in mind all the conflict and inevitable compromises you've mentioned.