If I were you I would let it go for the season. Let it Build a good root system and prune it in late January while night temps are still below 32.

In the mean time, water it well and get on a appropriate fertilizing schedule (sum organic slow release balanced blend).

In my opinion 31 inches is fine.

I would tie the ends of the branches to stakes when they get about 3 ft long and slowly bend (a little more each day, take your time) them to a 95 degree angle off the trunk (slightly pointing downward). That supposedly makes that branch produce a hormone to have it fruit heavily.

You don't want branches casting shadows on one another so keep that in mind when selecting which ones to prune.

I will only tell you what we did with ours, here in Oklahoma. First of all the tree was overgrown... too tall for my liking since we have a very small back yard. I had read a book by Ann Ralph, "Grow a Little Fruit Tree". You can Google it if interested. She and several other Nursery people advocate summer pruning to control height. The idea is that if pruned at the summer solstice, about June 21, the tree has used up most of it's winter stores for strong growth. June is the time to prune for height and winter prune to take out all growth that is crowding the center. We now have a four year old peach that is 6' tall and loaded with fruit. It has 4 scaffold limbs that are maxed out at about knee height. If I were doing this again with a younger/smaller (5/8 caliper) tree I would take it down even lower so we could have more fruiting wood within that 6' to 7' height. Another thing to look at would be videos made by Dave Wilson Nursery on this subject. Google "backyard fruit". Hope this will give you some ideas to think about.