What do you think of King Aegon V’s reign, leaving aside your apprehensions about Summerhall. Is there enough to judge him as a decent King or see him as another failed good-man-in-power a la Ned Stark?

My opinion about Aegon V has changed as various retcons (War of Ninepenny Kings) and new information (WOIAF) have come in. For example, I had long thought that the War of Ninepenny Kings was an example of Egg learning from what he had seen as a child, and choosing to act swiftly rather than let Maelys make another crossing into Westeros. Instead, we learn that Aegon V fought a well-executed but unfortunately not definitive war against Daemon III, and then ignored the Band of Nine. 

I think Aegon V was in many ways ahead of his time, both in terms of what he wanted the monarchy to look like and what he wanted to do with monarchical power. I think his reforms were well-intentioned and would have represented a substantial improvement for the smallfolk of Westeros, but it was probably something of a mistake to try to enact them before establishing the coalition that would give them weight (that’s the order in which the WOIAF seems to suggest it happened in, although the WOIAF is problematic in organizing information so it’s possible that’s not the case). 

I do think we have to critique his mishandling of the marriage alliances. With the Baratheons, Tyrells, Tullys, and Redwynes united to the royal family by blood, I think Aegon might have been able to quell the rebellions and make his reforms stick. Instead, he had to fight new rebellions, and his reforms were undone by his own son and grandson. 

And in the end, I think Aegon was a frustrated king, who could envision a new world more clearly than he could bring it about, who decided to do something terrible for the best of all possible reasons.