I would get a generator if the choice is that you can only have 1 of the above. In the summer, I prefer to park in the shade if possible so mostly to keep things cool enough the AC isn't necessary. I have the inverter generator capacity to run the AC but don't find it a very good option.
You'll find it also tends to vary a great deal as to how much good sunlight you'll get over the course of days, or even weeks which can result in your wishing you had a generator.
That said, I personally aren't all that much of a fan of generators and prefer not have to use them. That means something like a fairly large battery bank, more than likely solar, and a generator for when needed, which hopefully isn't often.
How's that for "It depends"