I agree with the cartoony thing as well, but thats really just a personal preferance. Otherwise tho I love the detail and the Iron Hands recognition on the model. Great Job.
Lovely looking model, perhaps slightly cartoony (because of the size of the weapons, and how they obscure the model) but I think that appropriate for iron Hands. The only thing i would say looks out of place, is the Chaos iconography/armour edging on the leg greaves...