> I loved that Lego was even units so you could end up having two things half way across your universe pretty much line up perfectly, or require just a few adjustments.

This fact is extremely under-appreciated: the Lego system works the way it does because they have attained truly astounding tolerance control in a cheap injection-molding process. I remember a couple of years ago when a small startup promised a Lego-like replacement, but themed for girls. The hype got them plenty of sales, but the poor fit of the pieces meant lots of disappointed customers.