Althought nowadays it's more common to see Everton's away kit in yellow or white shirts with blue shorts, during many successful seasons (such as the 1938/39 season, when they were crowned English champions), Everton wore a combination of white shirts, black shorts and white (or blue) socks as their away kit. I think that bringing back this tradition would be definetely a good idea for Umbro, who are well known for their traditional approach to kit designing.