I'm not very good at identifying what I like or don't like about many things, but I'll try to look at them and answer that anyway. Sorry if it isn't very useful or detailed since I'm just going to stare at them and try to think of what isn't to my preference.
The Phantom is pretty cool with me, I don't think I have any major problems with it, but I would like color variants of it.
Something about the Operator just looks . . off to me. I don't really like the 80's(?) square CCTV scope or the weird rectangle next to it (which I believe is supposed to be a replacement for the scope cover flap thing most skins have).
The Spectre I'm not too sure about. On one hand I don't really see anything I'd dislike about it, but I also just don't like it that much either. Once again maybe with color variants it'd be different.
The Sheriff is weird. I kind of like it, and it sort of looks like the gun in Control (the game). At the same time it's somehow maybe too blocky, but the cylinder being . . well, a cylinder clashes with it.
Oh, and one thing that sort of applies to them all is the strange floating circular trigger. It's pretty funky and I kind of think it's neat, but at the same time it's just weird, especially with how rectangular and angled all of the weapons are otherwise.
It'd kind of clash with the skinline's point in general but I'm sure if they had even basic, unique effects when firing (and maybe reloading?), they'd also be more popular. I'm aware not having those is kind of the point of 'cheaper' skinlines, but I do think something like that would've helped if it was one that fit the aesthetic well without compromising the concept.