Is your Chapter Champion's power fist his counts-as thunder hammer?
I really like your lava effects! I think you've got a very good grasp of the principles of light, which is necessary for good
OSL. I'm actually going to refer people who screw up
OSL to these pictures, in the future. Seriously. Good work.
Your shading and detailing work is second to none. Faces are exceptionally hard to do, and you've even managed to work glow-shading into the eyes (which is even harder than pupils/irises, something us Salamander players can usually skip

) You clearly chose the hard option, and I commend you for taking the extra effort. (You even managed to paint the aquila service stud well enough so that I can see what it is! Great job!) From the chains to the belts to the purity seals, you have an amazing attention to the minutia.
Did you make the Salamanders badge on the beakie guy's shoulder yourself? I only ask because I notice that's it's raised, which means (I assume) that it sticks out from the shoulderpad. I also noticed that it lacks fangs, which makes it a little less fearsome in my opinion. Although, if we're putting all the cards on the table, it's a billion times better than any I can do. (I've tried.)
I did have someone once try to claim in a tournament that my honour guard wasn't
WYSIWYG because, in his opinion, I hadn't modelled artificer armor well enough. You also appear to be using regular power armored marines that you've dolled up (and nicely, too!) so I just thought I would toss out a friendly warning that such tosspots exist.
Not sure how I feel about the white helmet. I have never seen Salamanders do the white-helmet-for-veterans thing before. Not saying I don't like it, only that I'm on the fence about it.
The guy on the right and the guy on the left don't seem to match when it comes to the shade of green on their armor. (Discounting
OSL.) From what little I can see on the guy on the right, his looks a tad darker than the guy on the left, whose armor is a little brighter than I am used to. I think it's the difference of a tiny amount, though, and if it looks good on the tabletop, then rock on.
On a personal note, I prefer my Salamanders mutant black as opposed to African black, but that's a matter of taste. As long as you like the skin tone, that's all that matters.
For all that, they are a boat load better than mine! Great work!