What white rock cross should I allow my hen to sit?

I have a broody hen who is driving me crazy. I finally decided to give her some eggs to hatch. My rooster is a white rock. The eggs that I've been giving her are EE eggs (blue). What are the chances that the chicks will end up laying blue/green eggs? I also have welsummers who lay lovely dark brown eggs. Would a white rock/welsummer cross give a dark brown egg layer? Or maybe I should just purchase some eggs on-line and give them to her to hatch.
Any advise? I really love the colored eggs - they practically sell themselves. I have not been happy with the Ameraucana hen - she is hysterical most of the time, now broody and before that laying yolkless eggs. My white rock hen just finished hatching out runner ducks and I don't think she is laying yet.