I would be happy with a voting age of 16, serving in public office at 26 and no voting or serving in public office at 70.
Sixteen year olds have the most skin in the game from the standpoint of having to live with the consequences of election outcomes. Sixteen year olds were allowed to vote in the Scottish independence referendum for exactly this reason.
Full brain maturation (fronto-cortical pruning) is not finalized until 26.
The incidence of cognitive impairment goes up significantly at 70 years old.
As I've gotten older (65M), I find that I have grown less hurried and hasty to judge.
Hurrying and rushing really doesn't help me to do anything faster or better, so why bother?
You do need to be able to quickly judge and assess people and situations in many settings and for a variety of reasons. That being said, I find that judging people prematurely can fail to appreciate their extenuating or particular circumstances. Everyone's got their own lives, problems and situations. For that matter, everyone can just have a crappy day. Doesn't mean you have to take crap from people, just helps to give the benefit of the doubt where and when feasible.