Hi Alan,
NG Development does pose its challenges.
I have used a Configuration over Customization approach in my NG Skin Development.
With the intent of only developing and maintaining a few NG Skins.
I have found the constant uStore upgrades that deploy a new NG Skin challenging to manage for example 12.1 and then the resent 1353 patch upgrade.
If you develop lots of NG Skins you will have to spend a lot of time upgrading each skin unless you use a configuration approach in my opinion.
Don't get me wrong I think the new react based NG Skin is great, however Demo's and the real world can be poles apart.
AFAIK Storefront JavaScript only works in NG Skins when legacy pages are accessed.
Regards,
Wayne