I have been trying to find the quote from the metaphorical horse's mouth, but haven't been able to put my finger on it.
I believe this functionality is already in the new update, at least in some format similar to the one you describe. If you want to play about with stuff like this now, you could try editing the mission definitions and ship variants within the existing mission structure to give you exactly what you want.
It's easy to edit existing mission definitions, a bit more difficult to edit ship variants, and a little bit more complicated to create new missions / ships. It's a bit of a faff around, but not too difficult, and once you have got the hang of it it comes very easily.
If this does interest you for now, check out the modding sub-forum, there should be plenty to go at within there, and ask around if there are any specific problems you come across.
