I found a very short article written by a figure artist, and it was pretty informative. It detailed the basic process from start to finish, but I'm really interested in artistic variants (paint schemes, sculpt changes) and how they came about, less so, production variants. Can anyone point me in a good direction?

There is an interview with one of the guys who produced the ledy line somewhere. I will see if I can dig it out.

This ventures more into preproduction steps which is an area I do not focus. I would recommend speaking to Steve Dwyer (dark artist) or Oli (olisuds) as they are preproduction/proto collectors and would have more info on the subject.

Thanks, I'll hit them up

There is a seven part interview with gi.Joe sculpter Bill Merklein on YouTube . It's not vintage Kenner but it's the best interview with a toy sculpter I have ever come across and he explains about the whole process of design , sculpting and marketing . https://youtu.be/NmgQeduUFW4

Thanks, I will check that out. Im interested in the entire process. Though what I'm most curious about are how intentional variants might come about. What was the inspiration for giving Luke Bespin 3 primary hair colors, or changing Yoda' s snake from orange to brown? And who made those calls? I'm interested in separating artistic from practical or manufacturing variants. Like hollow cheek Sandpeople seems an obviously practical choice. The little bit in the mold that would keep those tubes hollow would seem to be easy to break, and why make a new mold? Instead just modify it, and no more hollow cheek tubes.

But then there might not be definite answers to find.

I had completely forgotten this article by Tommy Garvey.
http://blog.theswca.com/2015/11/how-star-wars-figures-are-made-birth-of.html

It doesn't really talk about how variants occur, but you can see every step of the preproduction process. I don't think there is an item that exist to explain the small variants like what I think your asking about. Collector lore such as lucasfilm wanting this or that changed, the factory itself taking early liberties only to be corrected by kenner later, etc.. are all stories I have heard, but I am not sure how to trace them back to anything specifically. I have never seen a memo from kenner to a factory explaining the need to change Luke bespin hair color for example. If these are the run changes your talking about that made visual different variants, I will be honest and say I have no idea where to direct you.

That link is great, and lots of other links to follow. Very much appreciated. You are right though that some of the history of curiosities I'm really interested in are likely lost to time. I'll keep looking for a while though. It's all part of my obsessive personality. I want to know as much as possible about the hobby, however unimportant the details are