Dunno about the windows, but it is not uncommon to use a lesser grade flooring in the upper floors. As to hardness, how dented and beat up is the Florida pine? Which might be another name for hart/hard/heart pine and that is a very desirable flooring, according to Norm Abram.
Do a search for heart pine, which I believe is what you have. Also known as Southern Longleaf Pine. There is no more old growth of this species extant, so your Florida pine floors are quite valuable.