The weathering really brings it all together mate, you did a great job for you first go. If you want to put in some browns and other colours, instead of using paint get your self some pastels/chalk and rub it in with your finger. Once you put the clear coat on it looks really good, thats what I did on my armor.
Why dont you pick yourself up a cheap airbrush? They sound complicated and when I started my fett I didnt want or think I could use one, so much so I spent nearly a £100 on rattle cans that are now unopened in my workshop. But I gave one a go and they are brilliant, you have so much choice in paint and you can get the exact color matches for Fett. They are also a lot more controllable so you can get perfect shading and weathering. From how good your armor came out I think you would benefit and surprise your self how good you can get things to look with an airbrush. Then there will be no need to commission people to paint stuff which you can do yourself.
Welsh