As I recall, Cream Legbars are essentially a Golden Cuckoo... except based on a different color. I believe the Gold Legbars are a golden cuckoo, and as I recall Golden Cuckoo is generally wheaten based. I don't recall which base color the "cream" part of this equation denotes.
As mentioned on the Legbar thread. The definition that I saw for Crele was barring over a wild type bird (brown- salmon breasted female, and black breasted males which chestnut hackle, saddles, and shoulders) which is exactly what a Legbar is.
That means that Silver, Gold, and Cream Legbars are ALL crele colored since they are all wild type (e+/e+) with different modifiers for the silver, gold, cream hackle colors.
In the Marans breed Golden Cuckoo is defined as barring over a black copper Marans base color. In the Marans breed they don't use Wheatons for the Golden Cuckoo variety, but I have seen barred Wheaton marans and barred Black-Tailed buff Marans which do look a lot more attractive than the barred black copper marans in my opinion.
Campos confirmed in his studies that the Marraduna Basque Hens are a barred Wheaton variety. You can compare them to Golden Cuckoo Marans and Legbars.
Also, I think that the Double Barred Lemon Oprpingtons are barred wheaton base birds with the the same color modifier as the the Cream Legbar (Ig). I know "Ig" is required for the lemon color is some breed, but don't know specifics on the Orpingtons. "Ig" turns gold feathers to a cream color, and Ig + an additional modifier (name?) is required for Lemon color.