If you have a family, maybe. But for just two retirees, much less is better. That's just space you have to heat, cool, repair and clean. I don't know if you watch HGTV or not, but I'm noticing something of a trend afoot along those lines in the real estate shows. At some point, more isn't better, it's just more (work, money, trouble, hassle).
LOL. Three or more bathrooms sound good until you realize you're the one scrubbing all those toilets...