1,600 seems to be a good size for a family of 3-4, IMHO. Design/layout is obviously key, and with a well-designed house you could definitely get that down to 1,400, comfortably. We rent a 1,600 sf house. We are two adults and one toddler, and it's really more space than we need. There is an entire guest bedroom that only gets used when guests visit, and a large front room with a futon that isn't really necessary (unless even more guests visit at the same time and we need the extra futon).
MsPeacock, as in your neighborood, ours is also full of older houses on small plots of land, and everyone likes to expand their house up and back. It's an epidemic. At no time during the year are there less than two houses being expanded on the block. Everyone adds huge bedroom suites, extra large bathrooms, etc. But when you drive by all the houses at night, there are rarely any lights on upstairs. People spend most of their (awake) time in the downstairs living areas.
My ideal home would have a well designed open living space, with enough room for our family, but not so much that we will keep filling it up with unnecessary furniture. Some storage space (basement, garage, shed, attic, whatever) is obviously useful, but again not so much that we are never encouraged to purge. In general I think bedroom and bathroom sizes in America are way overblown. A bedroom only needs to contain a bed and a couple of dressers; for a child's room add a desk and a few other things.
