I think the future of the codominant morphs is simple and will follow the same trend as leopard geckos have (Mack snows) - the base genetics will become cheap, but combination morphs and selectively bred, stunning examples of a base morph will retain a much higher value. A pastel that browns out heavily and is almost indistinguishable from a normal at adulthood will wind up being worth about the same as a normal eventually... but one that's been bred from a line that stays bright and clear coloured will be a lot more valuable - not just because they're nice looking in themselves, but they will also improve the results when they're bred for combinations.

And I don't see a Butter Super Pastel Spider Pinstripe Granite Albino going for pennies any time soon either.

Recessive morphs will reduce in price slowly - they're harder to produce, since you need two gene carriers to tango - it'll be a long time before you can pick up an Albino Royal for £50.

Keep in mind also that not ALL corn morphs are less than £100 - there are still base morphs which have quite a high value as they're not very widely spread yet. But we'll see rapid decreases in prices on corns faster than royals simply because corns routinely lay clutches much larger than royals do - so a quadruple homozygous recessive morph is just a matter of picking the right breeding stock and having a bit of luck. I have a pair now that have 1:4 odds of producing double homozygous offspring, 1:16 odds of producing triple homozygous and 1:64 odds of producing a quadruple - Amelanistic Anerythristic Lavender Stripe, AKA "Glacier Stripe". Not EASY odds, but well within the realms of possibility for a 16-egg clutch, and given that corns can pop out thirty AND double clutch successfully, I'd put reasonable money on hatching out at least one Glacier Stripe in my breeding female's lifetime and possibly within the first two or three years she's bred.

I wouldn't place that bet if I was talking royal pythons and the same quadruple-homozygous animal!