Default enabling marks example font-family mark on paragraph nodes

[vtechguys]

I was looking to achieve the same functionality as Google Docs with font-family, font-size. I saw that the behaviour is very different here.

1. Missing the default* font-family?
   How do I start with a default font-family mark in the editor, i.e., when I start to type, it has those font-family and font-size marks already applicable? Every new paragraph and heading should inherit from the previous if marks were absent.

2. Inherit from the previous mark?
   If in a running text I change the font family and continue to type, then even the next paragraphs should inherit the changed font-family.