I have that here. Arizona in the summer. 105°F in the summer is a cool day. 110°F+ is common. But the local lake is green on top and cold (but clear) on the bottom. Usually somewhere in the 50°s.
As others have stated, get the gear ready early. I have been known to prep everything at home. Pull it out of the car, show up, turn on the air and it is ready to go. Why suffer trying to put everything together and test it in the heat when you don't have to?
Drysuit suit up is legs first. Suspenders to hold it up. Arms tucked into the suspenders. Under garments may be on or off the upper body. If not fully dressed, tucked in the suspenders like the drysuit arms. I can wait in this condition for a fair bit of time (boat ride, surface interval)
When ready to get wet, finish dressing quickly and slip into the gear. Only a couple of minutes and in the water. You have to plan the variables. Will it be a long walk? Can you set the gear by the water first then dress up? Can you park right by the water? Boat ride?
As for the breathable drysuits, I picked up a Ursuit BDS. Does it help? Well it doesn't hurt. I think it is better than my old suit. But won't cure it completely. Not worth it to replace what you have, but something to consider if buying new. I am unsure how much I feel from the evaporative cooling compared to anything else.
Something I found that is odd but helps. When you get out of the water don't break the vacuum pack right away. As the suit evaporates dry it cools. Keep that close to the body, don't fill the suit with a bunch of air (which is how you stay warmer). Get out of the gear first then break the seal. Undo the upper body and go back into the arms in the suspenders so they are not dragging the ground. And off to the next step (hauling gear, finish undressing, whatever the plans call for)