How is the younger Costigan going to be any different than the one we have now?

Well, he'll have less political experience.

Costigan I love as a storyline, because of the idea of humanity on a whole coming off the Messer regime, where it was unquestionable: anyone in charge is going to have the last name Messer. So we finally got away from that, and we're coming up to this first chance to vote for back-to-back Imperators named Costigan. A lot of people have an intrinsic reaction to not liking it, but there are some people in the verse who want that clear dynastic kind of inheritance and are drawn to it. And a lot of people are saying, we shouldn't even consider that, but just take the candidate on his own merits.

He doesn't have merits.