I think you've got the right idea my friend, and analysis/exploration would be appreciated by many here. I'm also a Southwestern US inhabitant and have been checking out my native/introduced species of Acacia/Mimosa. I think your first stop is the Trying to Improve Acacia information thread, and looking into what Nen and others have compiled on various species of Acacia/Mimosa. There's lots to be known!
Closest native Acacia/Mimosa I have near me is A.greggi. Not sure to what extent you have kept an eye out, but atleast in my climate, introduced Acacias run wild, so they're interesting to check out if you haven't.
I think it is really valuable to look into endemic species though, and info you glean would be appreciated. I don't know much about those two species, else I'd chip in.
Living to Give