I'm jealous :-) want my honest opinion? you have already shown this incredible tree all the love and care it needs. I'm flattered you came to me with your question, but to be honest, I don't have anything smart to say. I have no doubt that both you and the tree have won - each other. But enough bla bla, let's take care of that beautiful ornamental apple tree.
Background - you told me that your 25 years old tree was neglected and pruned hard (by its last owner). You have now decided to save it, brought it home and replanted it - lucky him.
So, looking at the big picture and considering history, age, location, and the look of the tree my apple tree pruning advice at the moment is - do nothing.
From my perspective, and I think you'll agree, our main goal is to make the most of the tree, and not just in terms of fruits, not at all.
We would like to enjoy the look of him and perhaps his shade for many years to come. In this case, all you have to do is keep him healthy and happy. So what should be done and when?
Let's start with the when - Not now! I've already mentioned the reasons,(new home, pruned, already started to grow = spring etc...) Because our part of the treatment deals with pruning, wait until next season. Your next pruning act should only take place during dormancy or just before spring begins.
The 'how' is marked on the picture below, just follow the marks...
White lines - just marking the size of the cup you wish to keep. nothing special here just showing you the structure you should maintain.
Green circle - shows the center of the tree which is in perfect condition and that is how it should be. wide open, clean, no crossing branches, perfect.
Pruning - Red marks - represents the cutting points or the branches you should remove. By removing these branches you'll get more balanced growth and a balanced look.
As for the upper part, I have decided not to provide you with any instruction. for now, I would like to keep it as is and next winter, soon after all leaves fall, please send me a new picture and we'll move onto the next step.
I hope that helps...
Providing general guidelines on 'how to prune' any kind of plant is important, but there are plants, and there is YOUR plant. So despite there being loads of information on this site, I also provide specific and personalized support. If something wasn't clear, or you're not sure of your plant's name, simply send me a picture with your question. Use the form below and I'll get back to you. In the mean time, see what others are asking.