The worst thing you can say is that someone's art isn't good.
It's literally his first attempt and you're already railing him like he was in an art competition, this isn't Whiplash.
Good artwork doesn't require a concept, especially when you're still learning how to crawl, let alone walk with posing tools.
His camera angles aren't anything to complain about when he's spaced the characters out and doesn't know how to properly use it.
And lighting is cancer in gmod. I can see why he hasn't used it, you need
@georgeebizzle to walk you through it before you can get good lighting on a poster when you still don't know how to pose. Let him learn the easy shit before he dives into the deep end.
Also, that small golden rule can piss off. Some of the best artwork has been art that relies on empty space to tell a story, wastelands, isolation, vastness, all shown by giving the viewer just one subject to focus on, with everything else ghere to make it stand out.
Like holy shit the poses aren't even that bad for a first try.