FULL DISCLOSURE:
When you put yourself out there, you are open to criticism, so please don't take it personally.
Me, I'm not an expert, I'm not professionally trained, nor am I licensed to train or even to critique video clips of other folks who shoot, but this is what I see.
Everyone looks comfortable with a handgun, which is a good start, and not to be taken for granted. In watching this group, I don't get the idea that it's an unsafe bunch of folks to be around. I think we can all agree that we can't always say the same thing from ranges we've visited!
I'd say that black shirt guy seems to be the most natural, he looks like he knows what he is doing, is doing it safely, is doing it to the best of his ability and he also doesn't appear as though anything he is doing is for the benefit of the audience. Red shirt guy is much the same way. Hard to figure which of these two looks more relaxed and comfortable with his shooting, but I would lean toward black shirt guy.
On the far other end of the spectrum is orange hat guy. Orange hat guy seems like he has some mental idea of what he's "supposed" to look like, what kind of rigid form he's supposed to lock his body in to, he got this aggressive lean that actually seems to become even more of an aggressive lean, and he really looks like he's got his mind LOADED with trying to look like he's doing it a certain why. I won't go as far as to say that he's trying to show off, but it just appears as though he's trying to make his body conform to some idea of how he's supposed stand and shoot. And it doesn't look like he has refined whatever stance he's trying so hard to accomplish. He moves, he flinches, and at the least, it's got to seriously interfere with quality shooting. It also doesn't look very comfortable.
Blue shirt guy seems like he's not done a heap of shooting, but he looks comfortable enough and it doesn't appear that he's putting on a show like orange hat guy, but he also doesn't look like a fellow that shoots a lot like black shirt, red shirt and orange hat.
Girl seems comfortable shooting, but her stance wants to tell us that she thinks any/every gun is going to recoil like a .500 Mag. Even though she knows it does not, she still has a stance that prepares her to resist getting knocked over. I think she'd have more fun and shoot better if she had a more relaxed, natural stance.
If I walked up on this group, I wouldn't get the heebie jeebies that someone is going to get hurt. (if you go to public ranges, you know the folks I'm talking about) The two folks that stand out are black shirt guy and orange hat guy. I would imagine that orange shirt guy probably has the most experience and knowledge of shooting, but feels like he's being looked to as the "boss" of this group, and he's not entirely comfortable in the role. Black shirt guy may or may not be a seasoned shooter, but he's got much more focus and relaxation when he's on the firing line.
I won't pick apart trigger control and specifics of stance because I'm not qualified to do that, and the video is a little blurry anyhow.
As for me, I'm quite sure that I've looked like each and every one of those guys (probably never looked like the girl!) in my years of shooting. Probably looked like orange hat guy a few times, too, but quit the moment I was cognizant of it!
As for what I see, I may be full of it in my assessment. But that's how it looks from here.