The unit limit based on resources sounds awesome! What a great idea.
Not so awesome.... why would I need more iron to support a tank... as long as it's not destroyed or being repaired there's no need for more iron.
Well at least they are trying to avoid those annoying old problems.... like:
Ohh great, there's some rubber on that jungle square over there, I'll take that frikking city and use those resources... YES I'M A GENIOUS!
*takes the city and makes a marine*
GOD DAMMIT! where did that rubber went??, OHH RIGHT.....rubber runs out eventually, but... but that fast? -.-