Congratulations! very well done.
As for you culling idea, It will be a bit of time before you notice any true deformities, almost all colour oddities in clowns are genetic. And often have no negative impact. Pigment and body structure development are similar but not the same. You will see many many perfectly formed clowns with bizarre pigment "deformities" yet functionally they are perfect, aesthetically depending on your views they are not. (Snowflakes, Platinum, Misbar)
On the other hand you may get specimens with perfect bars, pigment tones etcetc. but terrible face, fin and torso deformities. These are often linked to one or two things. Inbreeding, the first. With captive clowns its all to common to get pairs with identical or similar genetics. If they are wild however you'll be far better off. secondly the environment can play a huge role. Just as children while in the womb or early childhood can have adverse reactions to things, so can a fish. Often culprits are an excess of nutrients in the water which will negatively affect the bodies growing process by reacting with tissues and bones. Sometimes though there is more, if any aerosols or heavy produced substances make it into the water column its quite likely you'll have a structural deformity happen. Like clef lips in humans, A deformity that is because of the mothers contact with a particular gardening product. (from memory dont quote me! my brother has this)
I wouldn't cull based on incomplete pigment, this can be present until they are 5cm+ in length, rather embrace those. As they are how different demographic "morphs" often form naturally in the wild. Like Gold stripe, White Stripe, Lighting Stripe Maroon clowns. All the same fish with healthy body structure. Just different pigments.