Buildings as a concept are a good idea. It is actually important to simulate institutions and physical infrastructure and Victoria 2 didn't have much of it. It was, ironically, an abstraction that you could simply increase pop funding and use a national focus to grow pops. In reality, there is an essential physicality to the growth of the state. It is no mistake that one of the first things modernizing rulers in non-European countries did in the 19th century was found institutions like universities and bureaucracies to consecrate their efforts to transform their countries.
As an implementation it remains to be seen. There are things I like, like the physical usage of paper and the tying of pops. There are things I worry about, like the lack of regional bureaucracy, but it's still early so who knows.