I'm no veteran, but I CAN tell you of a whole new world of possibilites I was introduced to recently, which is basicly the use of limb pieces as armor pieces. It can add nice variation to the look of your MOC, and I highly suggest trying it. Oh, and I also suggest trying to use masks as armor pieces, as I have found that any duplicate masks you may have work nicely as shoulder armor.
Oh, and never be afraid to step out of your comfort zone. I recently did so by attempting to make a waist that moves and fits in seamlessly with the upper torso of my MOC. It worked beautifully after numerous different styles. I also recommend taking a look at other Bio-MOC's for ideas, styles, and even inspiration.
Edited for Double Post - Waj
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