If it is only inbreeding depression you are trying to eliminate, a better cross might be to buff. Buff is also based on e^Wh.
Black can be on either E or E^R. While you can get back to e^Wh from there, it might not be so easy to get rid of unwanted melanizers or other genes under the black. On the other hand, with the buffs, you might be fighting off-color in the male breasts for a while. Either route will require care and effort. I guess I would go with the best bird(s) I owned or could access. Here\'s another thought: why not bring in someone else\'s line of wheatens or blue wheatens? To me that seems the simplest, least time consuming, and least costly in terms of numbers of birds that must be raised to achieve the goal.