Imo, the texture is too big. ( or too small depending on how you look at it ) Better, I think, would be to texture paint the basic texture in blender, adding more rust around the seams, then do some filtering, and perhaps some more painting in Photoshop or GIMP.
(edit) also a peeled/weathered paint effect could be good. There’s a link to a mini-tut in my sig that would be a good way to do paint / metal blend.