I meant that the font tab is greyed out ... I really like do not want to limit the user so much! It will only backfire.

Oh man, I can't believe I am such a unicorn with my use case. Seems naturally to me to not want to important other styles into a document when pasting while being able to paste blocks of text containing images (therefore "pasting as text only" is not an option) and while still allowing for manuall changes via the font tab.