I find issues with about 1% of them...it sucks, but, it is part of nature...
In the past I have seen random cases of spinal kinking.
Not all deformities are visible though...last year (2021) I had two from the same clutch 2/9 that failed to thrive: I euthanized/necropsied one and used the info I gathered (deformed esophagus) to keep the other alive and comfortable as a 'special needs' pet.
This year (2022) so far it looks like I may have one with a stub tail (on my GHI Line).
Outside of expected deformities associated with specific morphs-I have been fortunate not to see eye-stuff yet (bad pun intended lol).