Designer fisht are "culled" in nature at nearly 100% ... hence the ridiculous prices charged for them when the 1 in a million survivor is found, bred, and, initially at least, the very few that look like the original morph are then paired and bred ( lather rinse repeat ) to extend and "improve" the "non-desirable traits " ( non-desirable from Mother Nature's perspective .... if she wanted Picassos or Snowflakes or Photons or whatever, do ya think she might have had a few millenia to populate the reefs with them? ).
That said, people want designer fish, desgner dogs, ugliest dog on the planet, whatever ....... there is a market for the misbarred, no barred, inconsistants, etc so if you are of a mind to do so, step up and breed these and sell all you can. Morph your corals with lighting, electricity, etc and sell those oddities for all you can get as well.
The only hope is no one releases these into the wild and they might turn out to be some kind of serious problem if that ever happened ( might - might not -- ask the Australians if they would introduce cane toads, exotic elms, parasitic wasps, etc if they knew then what they know now )
However do recognize the 200-300 fish you "save" certainly do not result in "fewer taken from the reef" as these aren't out there or they would be in the wholesale path and stores by the hundreds.
It seems to me a bit disingenuous to cull any of these fish for "freakishness not shared by other fish of this type", or worry that the fish might be bred at some future point, when the whole population is "freaks" .......... ( freak --- A thing or occurrence that is markedly unusual or irregular ... designer fish are freaks when compared with the original line of fish ( true percs or false percs are the originals ).
And yes, we breed clowns as well so I get the attachment to the normals as well as the oddities .......... also, we had one of the first pairs of Picassos (won at Craze) and we had every intention of breeding them given the price at time was $300 per fish and I can always find use for coin of the realm (hypocritical to be sure given I don't think they should be bred or sold, but I certainly could of used the cash and it wasn't like I was violating one of the Big 10 rules or anything).
Unfortunately we lost them ( and a bunch of other stuff ) to a serious mushroom meltdown ( gorgeous tank at midnight, looked like a milk bath at 6 AM ... never did figure out what happened).
So, in late response to your plan, I agree these fish should never be killed. Someone will take them and enjoy them for a very long time. I hope you continue to raffle any other oddities you find in the future.