Hi Andrew, the washes look good but that is just the start. First , I would fill the ejector pin marks inside the grenade case, and then do some blending with various tones of oil colors [ I am assuming that is what you used] and maybe some drybrushing to eliminate "tide marks" where the washes end. As for wood grain you can paint that on with oils or acrylics. Try painting the wood a different color with oils and then drag a tooth brush, or a stiff bristle brush across the wet paint , therefore creating wood grain. Overall things are looking good, hope that helped, keep up the good work, Jim Rosado