you might want to try messing around with graveyard earth or a similar brownish tone, that could blend well with your green without standing out too much. You might want to mess with the scheme in dawn of war's army painter, if you have it, that definitely helped me out a bit. I'd imagine dark flesh/graveyard earth would complement each other well for your weapons. You may want to use your sept colour as a highlight to the weapons, for example the missiles on the missile pods may look good in your sept colour.
And missiles and plasmas are awesome weapons, it is just my opinion that they do not belong together. They tend to form a bit of a generalist unit, and the eldar in me is opposed to that