You don't need 2 generators. 1 with the right output is enough, 2400 or 3000.
We run the air when the evening starts to cool to bring the temp down in the rig for sleeping. A small 12v fan keeps the air circulating and works very well.:Z
We use solar panels ( Canadian Tire on sale ) to maintain battery levels.
With conservation, you shouldn't have any water problems.
We generally do the 3-4 day boondocking and then FU to top up and empty for a night or two. :C
We use a 45gal. collapsible water tank for extra fresh water if needed. Easy on storage space.
We have a have similar tank connected with a macerator to dump if we are staying longer. We fill these up or dump them when we go for supplies.
This is more for long term that you are not interested in at this time. We fulltime so we have it all covered.:W
My own thought is if you have to have the air on in the daytime because it's too hot in the shade outside during the day for you.....go to a FU campground. I prefer the ones with a nice pool for adults only. :B