Rick ... it sounds like you are handling container plants very well. One of the things I do that you did not mention is that I always lift the pots from the hardscape to insure good drainage. It doesn't take long for soil in a container to go sour when you use soil.
For my cuttings, I generally use a mix of perlite and vermiculite and no soil. Don't laugh, please, but I also sprinkle the tops of the cutting pots with cinnamon because it seems to prevent fungus issues and damping off.
My native soil in the garden is comprised of glacier slurry which has a LOT of small rocks tightly compressed together. Once I break up the soil for planting, I leave those rocks in the bed because I honestly believe they help with the drainage in my clay soil. I hadn't thought about how they also help with the exchange of gases, Thanks for mentioning it.
Smiles,
Lyn
