Great question Jim. I actually had to stop and think about this a little.
Maple is the most often asked for, I guess because of the cost and durability. (Just went to the lumber supplier yesterday and bought 240 bd ft of hard maple. Filled the rack a little. I guess I should have gotten 500 or more.) Walnut is the next most popular even with the cost and waste. Walnut is graded differently than other woods and has more defects and knots which have to be discarded or worked around. I hate throwing out scraps and walnut pains me the greatest. But the results can be spectacular! Cherry is the next most requested. I really like working with cherry because of the smell and how easily it can be worked. Add to it the natural tendency to darken as it ages and it can be beautiful. The only bad point about cherry are the pitch pockets, those little black voids that tend to show up in the worst places. I work around them the best I can but most are unavoidable. Also with cherry there can be a lot of waste due to those pitch pockets and limbs which mar the work. I did offer mahogany and still get the rare request but until I get a supplier who can get the same species I was using, I will not be offering it. It is a beautiful wood with the deep burgundy color and black highlights.
Only rarely do I get requests for anything else. I did make a cedar board for a grill once and it looked very nice. I get a few calls for ash and hickory but never any real interest. Once in a while I get a request for oak but so far no one has ever actually ordered an oak board. It is one of those woods that, IMHO, look like it would be a good wood to use but may be to porous to be able to clean properly. I suppose one of these days someone will order one.
You are correct stating that wood fashions come and go. I made a bathroom cabinet in whitewashed oak about 20 years ago and it still looks good, just rather dated. The darker stains seem to stay in vogue but hide the real beauty of wood. When mahogany is sold in the stores it resembles nothing of what it really looks like. With all the fillers and stains, mahogany looks more like Formica. Such a shame to see the beauty hidden. And when I was selling mahogany, I was asked why it didn't resemble the mahogany furniture sen in the stores.