This post is a moan rather than a specific question.
I built a city months ago and was gutted when the last update (before) only generated villagers on new maps.
So I was delighted that at last, with update 9 I could populate my old town that's been sitting waiting for months.
With the new spawn eggs I started filling my 100+ houses with villagers until...'you have reached the limit of villager'.
Damn you minecraft.
Why a limit?
There's no good reason. There's no limit of people on Assassins Creed!