I mean, it still takes at least a few months to get a claim, and you risked getting 7.5 AE (well, it's 5 AE now, which I think is good, as sometimes getting caught fabricating gave more AE than actually taking the province). I like that you now don't feel like you have to claim every province you take, as -10% coring cost isn't nearly as good as -25% coring cost was, but since the coring costs increased as well... Honestly, the best approach, I believe, would be to spread out the bonuses of administrative efficiency over 10 levels, where each level ultimately gets to the level that the second administrative efficiency gives now. I think it makes much more sense that nations didn't suddenly get way more efficient when it came to administrative, but that it was a gradual process over hundreds of years.