Thanks for promptly sharing this updated information.
First off, your blog is not clear what “customization” you are now terminating. Since I have read everything I could find on the new Annika head, I believe this is a reference to previously promised EXTENSIVE customization options. Far beyond what normal customers would be interested in (or willing to pay for). I.e., changes that business customers might want to make, for their own, unique, customized version.
If that is the case, I would agree with you that it makes sense for you to focus FIRST on getting your own version optimized. There will be time for the second phase later.
But perhaps I am wrong? If you’re talking about simple things, like skin color, eye colors, and hair, then I think that is a mistake. I can’t see any of those things causing delays in production. Unless your goal is to simply make ONE configuration, and keep it in stock… with NO customization of any kind?
I really feel you have not explained WHAT customizations you are now discontinuing. 
[Oh! And are the eyelashes really PAINTED on? On a Silicone head? That right there is a NO SALE for me:
Honestly, that makes no sense (to me). And the eye color is: “random”? That’s bizarre. At least I can easily change the hair, if I want. But how easy is it to change the eyes? My guess is: NOT easy, since they move! So no standard eyes will be compatible. But perhaps you can provide compatible ones for the User to change?
SUGGESTION: If so, just put extra color eyes in the box with each head. Then you can maintain (stock) just a single SKU. And the owner can still have what they want.
And BTW, Default is misspelled.
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