The essential problem with this system is that we are using a simple browser to search a very large and complex database. And it wasn't designed to be a nice, orderly, structured database. While some sounds have clues like instrument, key and tempo info in their titles, many do not.
It would probably require a whole new industry-wide standard to get genre, instrument, key, tempo and whatnot information coded into these files, but it could be a basis for solving this situation.
Meanwhile, back on earth, what about a way to at least mark good stuff once you have stumbled across it? The humble Cakewalk Sound Center has a system for marking sounds with a 5 star rating system, in addition to a category/sub-category organizational system.
It is frustrating for me to know that there is so much wonderful stuff hiding in my gigabytes of sounds, and I don't have a really effective way to get at it all...