i agree with last poster... paler green would work with dark green, we have that in our hall and it works....
i would disagree about a mirror in the kitchen though, a friend of mine has one in hers opposite the window, and it was lovely, gave great light....
have you though of putting in a sky light?
our kitchen gave us the same trouble, our presses are light oak with a green conter top.... we had painted the kitchen with ripened corn i think, however we changed it for a pale pale yellow colour and it has brightened it up no end...
i would also suggest a soft washable sheen paint, so that the light is not aborbed into the walls.... and of course, you can wash it...