My sewing area is in our master bedroom - but keep in mind that my master is something like 24x18. It's a HUGE room and comfortably houses a king bed, a dresser, two bookcases, my desk, a Horn of America Quilter's Dream cabinet that I can open and leave completely open without it getting in the way, a small table for my second machine, a cutting table that's set up at all times, an ironing board also set up all the time, and two end tables by the bed. It may sound crowded but it really isn't, and when I do close down my cabinet and cutting table, it is huge.
That said, I hate it because I am upstairs by myself all the time. If I want to talk to my husband, I have to go downstairs, and I feel somewhat isolated. My 18 yr old son spends a lot of time upstairs in his room when he's home, with the door closed, of course, so that doesn't help. And when he graduates HS in June, gets a job and is going to school and/or leaves home, it will only get worse. I've struggled with what to do about this, because I am lonely up here, and DH will support whatever I decide to do, but the only real place downstairs for me to move into would be the breakfast area. That means we wouldn't have a dining table at all (the formal living/dining is a game room with a huge pool table in the middle of it), and that doesn't bother me overmuch, but my son does sit there to eat when he's home. And the breakfast area isn't all that big ...
If I had a choice of the three situations you offered, I would go with the family room on the main floor. I love my alone time, but in this room, I get a little too much of that. This last weekend, I saw my husband for meals, when I would go downstairs for a glass of water, and about 2 hrs to watch a little tv with him before bed. It was sort of lonely, honestly.