I get where you are coming from I am not saying you are wrong. I myself see it as an exaggeration of the human form and isnt intended on being as accurate.
Older comics were inundated with over proportionate figures. (Kirby etc) I agree the spikes are cool since I use them but that wasnt his choice on this attempt and really doesnt fit the critique since thats a preferential thing. This drawing has a Kirby/Joe Sinott vibe to it for me.
I think its a good attempt and if he keeps it up, will do well.
Valid points from you, but it doesnt all fall together in a few sittings. This all takes time and its easier to point out things from the outside in, than to get all the pieces to look just right by the person/artist attempting it.
Good luck to him to continue improving on his craft.