One of my main gripes with the latter half of the series was the canonization of Delenn and Sheridan. I mean... okay, yeah, they've done impressive things and generally mean well, but it's exactly this sort of murky situation you mention here that got shoved off to the side. I would have loved to see it actually explored. (And I groaned during the S4 finale when that panel starts debating whether Sheridan was actually all that and a bag of chips, and old!Delenn shows up to smack them down because... we can't have anyone disagreeing with the One True Interpretation or something?)

I hadn't thought the situation through this far and made the Londo parallels, though. Argh, I don't have time to rewatch the show but now I want to!