hello there trying the hand painted style. the concept is from firstkeeper who is a Amazing artist! http://firstkeeper.deviantart.com/art/Weapons-concept-04-284014517 i hope I do it justice, here it is , and more to come.
You should try putting thin white highlights with hard brush over the edges of metal. Take a look at this texture. http://awesometextures.blogspot.com/2012/04/jessica-dinh-metal-texture.html