Less is definitely more with the weathering. I tend to try to only put one or two scratches tops on any given plate, and focus on the sharpest raised edges-- the elbow, the rims of the shoulder pads, and the top of the hand for the gauntlets. It's also pretty easy to soften up the weathering if it's too harsh with a little bit of powdered pastels-- you just have to seal the model afterwards. I'm also a big fan of Tamiya Weathering Master-- you can just work that stuff into recesses with the makeup sponge they come with, and it leaves a great finish every time.
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