Hello, fellow Southern Californian! I am not too far from Simi and often participate in dog agility trials there. You guys are defiantly hotter than we are on the coast. Windier, too.
Still, for our climate, I really think the open air coop is the way to go. I agree with another poster that said your old coop looks dreary. If it were mine, I'd take that entire south wall down to the studs and cover in hardware cloth, as well as the two side walls to about half way back. That would leave a three sided section in the back for roosting out of the wind.
My favorite example of this style coop on this forum is here:
https://www.backyardchickens.com/threads/texas-coop-build-pic-heavy.1371038/
I basically build a miniaturized version of this and have been happy with it for over 10 years.