We have a semi-dwarf Tropic Snow white peach tree (citation hybrid root stock) that we bought in a 15 gallon container and planted last April here in San Diego, CA. It's in the process of losing the last of its leaves, and I would like to prune it during its dormancy this winter. It's pretty tall with a strong dominant leader. I'd like to encourage and develop more side branches, both to dwarf the tree a bit and allow for a better framework and structure for the tree shape.
I've read that peach trees can handle pretty aggressive pruning. I'm just not sure how much I should cut as I don't want to kill the tree in the process. The tree is currently about 7 feet, top to bottom, and 3.5 feet, side to side.
Here's a picture of it (ignore everything at its base; we are in the process of having a new patio laid):