He then talks about how "You must be expecting me to..." Basically, that he hasn't sorted out all his new powers yet. And so, like, a little embarrassed, but not to lose face. It's adorable, I can't hold back a smile of cuteness at this point.
I love the way he says that bit, the pleasant smile when he says, "It's going to take awhile to become acquainted with my new self." There's no frustration or impatience or even a sinister tone. He sounds so confident and pleasant.
And yes to everything else you wrote as well. I do like that he gets a few cute "old Astarion" lines after ascension. Like the joke he makes if you hire the drow twins at the brothel. I think with time, he'll be able to reconcile the two halves of his personality.
