Will be fixed in the next patch
It's not listed under the Heavy Infantry cults
It's not currently part of the builder process, but you're right in that it's trivial to do once you've completed character generation
RAW they're not eligible for the bonuses.
Every sibling, male or female, is currently showing as a sister - this will be fixed in the next patch
Familiars are coming soon
In retrospect the toolbar buttons should be blue rather than white, to keep with the theme, I'll change that shortly. The red on the edit button is just to make it stand out, so I agree...it's you 😁
Thanks for all the great feedback