Knower of little, master of less.
Hmmm. Made one that goes UNDER the hood, for engine work, rests on ARB and that little shelf in front of the cowling. Hadn't thought of going over the hood. Now that you mention it, though, I seem to recall some African rigs with a setup like that--for photographers, as you say. Maybe hard mounts sticking through cowling? Going a little far for me, maybe, but interesting idea...Roof definitely won't support in middle. I cut a patch for the sunroof out of my parts rig, and left a nice dent in the roof, behind the cut thankfully, even before cutting. And I'm lighter, but not by much.
Can stand on cowl, but not recommended (again, did it on parts rig). You will dent it.
Just put a massive push bumper on it, that sticks above the hood. Then make a detachable platform, that goes from the push bumper to cowl. More distribution of weight, and creates a little deck. My friend did this, who's a wildlife photographer, but with a Tacoma. Same principle.