I'm steadily more inclined to think that the year ages need to be removed entirely from the UI and replaced with a plain-language set of ages (functional statuses), e.g. infant, toddler, child, marriageable youth, young adult, adult, senior adult, elder, whatever...

Having the dynastic ages listed in years seriously undermines the (good, IMO) basic decision to call a turn a turn, and not a 'week' like GalCiv2 does. If the dynasty needs a quantitative age for some zero-sum gamer reason that I've missed, why not just list it in turns? That would leave room for tweaking the underlying math about scions and whatnot without needing to tweak the UI as well.