You can get quite a few patternless snakes for around $800. Super mojaves are white with a grey head. Females go for around 800-1000. Males I've seen for 500! Awesome considering how beautiful and affordable it is !

Champagne is another good suggestion I saw . They vary so much, you could produce little-no pattern champagnes, or strange ones with buts of circles in the pattern! Very cool IMO!

Have you seen the piebald ball python? Google it, and wrap your head around the fact that you can get one for just 400-700 ...

Genetic stripes is another good idea .... They'e relatively cheap (for a recessive), and they can also vary!

If you're interested in breeding, maybe you can make your own patternless white or black snakes ..