My vote would be for two toilets if possible. At bare minimum a doorway from both the master and the hallway.

We are in a similar situation. We are putting a family washroom on the second floor of our 1950's farmhouse. We don't have space for 2 washrooms.

Personally - I HATE bathrooms with a door from the hall and the bedroom. Whenever I am a guest at houses with them I find you have to move towels, laundry etc. from the 'master bedroom door' in order to shut it (and lock 2 doors) and I am always in fear that someone will come in the second door!!

BUT - the suggestion you had with 2 vanities and toilets with a shared shower makes sense! (I remember a dorm room like that actually).

We will be going with 1 door from the hall, double vanity, single toilet and shower.

If 9.5x7.5 is as large as you can go, I would not 'spend' the space for a door from the master. I would, however, try to partition off the shower as well as the toilet, so that someone can be showering or using the toilet while someone else in using the vanity.

How many kiddos are there? We designed a jack-and-jill bathroom for our daughters where one can be showering and the other can use the toilet or be at their vanity. It is an L-shaped space with 3 doors (one is a pocket).

Also, two sinks would be really important for a family bathroom. And squeeze in as many drawers as you can, for toiletries.

It would depend on the precise layout, to make sure all the doors didn't make the space awkward, but in general I'd choose the second option. Two sinks would be critical, but having them in the same vanity wouldn't.