The current RDJ Tony is in a state where, though somewhat humbled, he's still primarily driven by hubris and his personal demons.

TIA Tony, though brilliant, was still very much in the grips of those demons - to the point of never really realizing there was a problem with that until it was too late.

UF Tony has been through the wars in a totally different way, and it's left him with a much different perspective. He's seen his entire universe go away, and he's been opened up to a lot more. I suspect that he's found some interesting serenity because of it - and let's not discount the value of having found a second chance at one of the biggest relationships in his life, either.