The first is that this show at heart is about the journey of the two brothers in reaching each of their own happy medium. Stefan started out "good," Damon was "bad." And we're seeing the evolution of both of these to a place where they can live comfortable in their skins without being OTT "good" or OTT "bad."
This is what Julie said on the Panel:
"The beauty of Stefan and Damon is that both of them, though one began the show as a hero and one began as a villain, is that in their core, they both have sides that are as dark and as light and that really fight against each other. And when you add the vampire context into it, it's a constant battle for both of them. For Damon, it's battling against the parts of him that want to be pure and good and for Stefan, it's battling against that sort of demon inside of him that wants to take over. So the brothers are sharing a journey. It's just manifesting itself differently."
The second was that while it was Katherine, the love the boys felt for her and how she handled it destroyed their relationship, I believe that it will be Elena, their love for her and how she is handling it that will play a big part in repairing that damage between the boys.
And Julie said this:
"I think the worst cliche is letting a girl tear two people apart," Plec said. "I think the smarter path is watching how, in spite of the conflict of that girl, how can it still bring two people together."
It made me happy because it affirmed my hope that I've been reading the character and arc intentions as has been intended by the creative team. So yay!