Some discussions are way over my head, but the most important aspect of koi keeping that I learned from this forum, an aspect all of you keep stressing time and time again with great conviction are: patience, maintenance and don't overstock.
I don't have a pond yet. I have a 600 gallon acrylic tank with only 3 fingerlings at 4" that was given to me by a friend when the fingerlings were 2.5" a few weeks ago. I'm taking it slow and will eventually build a pond with high quality kois at very low stocking rates.