kota1, thanks and that is a good question. If I knew back then... Well I wouldn't have wasted a year on HT, wouldn't have given away almost all my records, wouldn't have wasted even more years on CD. Would have run a dedicated line to the front of the room instead of normal outlets daisy chained all around.
But then all these things assume a knowledge base that was mostly acquired by hard won experience. Otherwise known as screwing up first to do better later.
So the number one thing I guess would be, if I knew then what I know now, I would have started screwing up a lot earlier.