Whatever direction you decide to go with this, I would suggest that you use a color that is compatible with the Blue (black dilution) gene as it is an integral part of this breed. In order to get a project to be considered part of the breed, you will have to back cross several times to purebred birds. Yes, you could always use black Silverudd's Blues to back cross to, but this breed was designed around the blue plumage color and the green egg color (requiring the blue egg gene) and it would be a shame to disregard it.
Also consider other traits when starting out. The Wheaten Ameraucana would reinforce the blue egg gene, but would add the pea comb, muffs and beards which would need to be bred out and can cause problems down the line.
Just some things to think about.