I always sort of expected wizard power to be on a curve. I'm gonna geek a little, forgive me, I ain't no English major. People who know me I am all BS (that didn't come out right....) . A curve asymptotic to both axes. Let the Y axis be the number of people, the x axis their power level. At near 0 power there are 8 billion people. Can't even get enough juice for Flickum Bicus. I think it was established there was roughly 2000 White council members. So... about 1 for every 4 million people. Yes, they miss an Elaine or two, but they likely have most of them. But when the Skavis was killing the Paranetters, Elaine said he had 36 she knew of. If they were also 4 million to 1, that is nearly half the US contingent (assuming US dispersion is the same as worldwide), yet there are still a handful in Chicago we see, and Elaine only knew some cities. Therefore, the low powers are more common than high power. More people with 100 IQs than 150s. So Harry is high-end. But that curve is flattening out REAL fast there. So a gain may not pass too many. Though we know he moves up with Morgan gone, and likely Simon Pietrovich, and LaFortier. Luccio said even in her old body she didn't have his raw power.
Harry is not top 30 or 40 in his age cohort. Gatekeeper said he was probably the MOST powerful of his generation in Turn Coat. That 30 or 40 is compared to the old guard, the Ebs, Rashid, Langtry, Morgan. It appears you gain power with age. Harry is getting there, but he is not there yet.