Flaws common to specific ponies?

[Taffeta]

I used to have Y3 AJ MOC, and I remember her hair wasn't really curled properly, just folded in half in the package. I no longer have her, but it doesn't seem like they went to much effort to curl her xD.

I wonder if it's also to do with how well the pony's hair is taken care of as well.

The UK CJ tends not to have problems but can have dry hair, rather than frizz. I have also found the y3 CJ here with curls that are fine. And then there's my puddleswimmer, about whom the least said the better...

Her hair now looks like she escaped from a 60s hippy rally, but when I was a kid it was mostly sticking up in the air in two directions like rabbit ears...

[Artemesia's Garden]

Several of the Twinkle Eyes often have yellowing/cancer these days: Gingerbread, Sweet Stuff, Masquerade, with Masquerade particularly prone to head/body mismatch as well. Whizzer I haven't seen with cancer but she almost always has the head/body mismatch. Galaxy is prone to regrind and head/body mismatch but there are still lots of good ones out there if you fix the hair. I think the most important things to slow these issues down are to make sure they are clean and dry and stored somewhere with ventilation at as stable a temperature as possible. My whizzer has a scarf.