Well, we likely have irreconcilable differences over what makes a great story, since I thought 'Batman: A Death in the Family' was an overrated, poorly written, cheap and mean spirited piece of crap. I admit that subsequent issues about Jason's death have been powerful (Underworld Unleashed, that issue of Deadman, etc...), but considering the nature of the Batman books prior to his resurrection I don't really feel like Jason's return undid anything that hadn't already been undermined by poorly written stories and poorly conceived ideas.
No, I don't think it was editorially mandated. I think there had been some murmuring of his return after his appearance in Hush, but I think it was all Winick's idea.