Let's discuss asteroids

There are many esoteric sides to astrology. The use of asteroids and planetoids is one of them. Chiron puts a perfect Grand Cross in my natal horoscope, which fits in so much. It makes a lot of sense being there (previously I had a T square, which I thought was bad enough). I have been torn to pieces by external and internal conflicts.
I know most astrologers only use the biggest asteroids, but since there are literally hundreds of thousands of them, where do we draw the line? It seems to me that if we admit 4 we must admit all of them, which would mean that no one would ever have enough time to do a single natal chart. And what do astrologers think about the reduction of Pluto to planetoid status?