I really loved Forever and I really wish it'd been renewed - so much great casting! (And you're right about the interactions).

I agree about it being life-affirming, and there's something fundamentally hopeful about it, even when they're dealing with difficult things. I haven't rewatched it since just after it finished, and clearly I should do that again!

I also found the flashbacks worked pretty well for me, especially in the sense of unfolding character backstory in a way that was more - patient?- than you often see. (Actually, much the same way Leverage does, if a bit less sparingly.)