Unfortunately, I think the Deep Dive will spend about 15-20 minutes recapping yesterday, or going into fairly generic information. That leaves at most about 30 minutes for delving into new info.
Hopefully they clarify Warbands, Delves, and give us more (all?) Hero Talents. I'd like to begin planning my Warband as soon as possible, down to the smallest detail.
But I think we'll come out of it still feeling like we needed more information. That just seems to be their style these days. Rather than detail everything like they did in the past, they'll keep a lot of stuff close to their chests so as to avoid disappointment if plans change before launch. The benefit of this, of course, is that we'll keep recieving a steady stream of exciting snippets of information throughout the first half of 2024.
Finally, I really hope they give us the 2024 roadmap for Dragonflight. Anything else seems borderline negligent at this point. We need to know what's coming soonish. New class/race combos and so on.