Good idea and I agree Julia, there is a big difference between a private bathroom down the hall of a host’s house and a private “en-suite” bathroom. And with an “en-suite” bathroom you don’t even need to have to state it is “private” because of course it is private – it is en-suite!
I also think that it is silly to have to choose a filter option for "Private" or "Shared" bathroom when you are hosting an entire house/apt. Because when you host an "entire" house or an "entire" apartment well of course the guest will have a private bathroom – because it is an entire private house/apartment.
Also I have often thought that there is such a big difference between private room hosting vs. entire house/apt. hosting that there should be an entire different line of filter options and also whole different sets of extra fees and amenities because they are so different. I am going to work on this idea and post it when I have time – unless somebody else does it first.