She means that Evo is acting much more civilized than she we would have in the same situation. He asks her how she is doing before she does, so she thinks that he is acting very calm about the whole thing.
Yes, she is definitely playing with the fact that Evo is acting very calmly and being polite with her despite the situation, and at the same time making a reference to his aymaran descent. Cristina is not known for being frugal in speech nor calm when in adverse situations.
I have spent a lot of time in Argentina. Argentinian people are very into being cute and intimate, even with people they don't know that well. There is a refreshing lack of excessive seriousness in that culture. If you know Spanish and have seen Kirschner speak she almost comes off as a goofball the way she cracks jokes and makes "cute" references to things, but it's really just a reflection of Argentine culture more than anything else.
Argentine here, CFK's way of speaking is a reflection of insanity, not Argentine culture. True, we take many things lightly but CFK goes way over the top, especially for a President.
In any case, the deep-rooted corruption of her administration (and practically all others decades before it) is a symbol of Argentine culture.
Yes. It's because of his being a leader of such a country with an old heritage (and of such origin) -- it's a reference to the (supposed) wisdom and patience that comes with that.