These are some great points. It would be interesting to have a rating system like that, no doubt, but I wonder how we'd score them. I would give a little more weighting to someone in academia simply for the fact they are swimming against the current and risking their precious tenured career, where it's a lose-lose. Standing wants to be famous on this topic, but I don't consider that a knock against him, but maybe I don't give more weighting for that.
Someone like Isdahl I give a little more weighting to because of his outdoor game experience, just like I would the experienced hunters I see on this forum. I don't think the "you just saw a bear" works on someone like that, especially coming from someone like myself who's closest wildlife activity is a raccoon looking for food on the porch at 1am. Serious hunters know the sounds, the behaviors of the animals, and know when something is off, or if something is perfectly normal even though it may look really strange to someone like myself.
I give experienced hunters or those that have spent most of their adult lives outdoors, like natives in Alaska, the most credibility. If any of them are liars, then I'd just consider that a small error rate that's baked into the cake.
Some people you just listen to and know if they're truthful. If they're psychic or "remote viewers", I'd just ignore them. Law enforcement and such occupations I'd give weight. Ex-special forces/ops, etc., I don't know because if you follow some of the stolen valor channels, it's insane how many of those guys lie, so unless proven to have such a military past, I ignore those. Engineers and such specialties I give some more weight because they can get into the weeds of the various aspects of this topic, e.g. Bruce Maccabee for camera stuff. Government wildlife eco guys, not as much because it's unreal how little they know when compared to hunters and serious outdoors guys. Some mother who runs across one with her kid, who's now scarred for life, I give weight.
I rambled, but it would indeed be a cool project to design and implement a rating system of some sort based on various factors.
One area where I disagree with most is the point of "we're going to need a body." I think people really don't understand how brainwashed some people are (not just on this topic), even when the data and facts are in front of their face. Until one is smashing their dog against a tree, or in front of them letting of one of their lovely screams, there's absolutely no way to convince them, and we shouldn't care about doing so. To put it another way, how many things do we know for a fact are real, but a segment of the population doesn't believe it? Why would this be any different?