I know what you mean about white snakes made with Yellowbelly. I'm going to run into the same thing with my BEL complexes. This year I'm pairing up my Bamboo with a couple female Lessers. I should get a few Blue Eyed Lucistics (BEL) that are the allelic Bamboo Lesser combo. The only problem with holding those back is if I breed them back to a Lesser I won't know if the white hatchlings are Super Lessers or Lesser Bamboos, the Lesser Bamboos being about twice as expensive. Plus if there are any other genes in the mix they are masked.
I've been considering getting a few pairs of different supers just to make pure supers, like a pair of Super Fires or Super Black Pastels. It would be neat to have a few on the tables at shows and to just keep the pairs together every season. White snakes and black snakes seem to have an appeal all their own.