Personally, having tried both MCCC and Neighborhood Stories... I don't like either one.
MCCC, as you observed, moves people around and creates some really crazy, messed up families. Neighborhood Stories isn't quite as bad, but I found it was too aggressive in moving, having kids and especially killing off sims for my taste.
In the end maybe I'm just too much of a control freak. I've turned both off except for a few specific cases where I'll turn Neighborhood Stories on briefly and then turn it off again when I've accomplished what I wanted (like when I wanted all the families in Henford to adopt pets but didn't want to hand-make them).
