Sure. You can shape your trees all kinds of odd ways.

I guess it is normal to think of the convenience of picking while standing on the ground. How about the pruning from a ladder as well as thinning. Does your sprayer do a good job with a taller tree? Most think of ground clearance to be able to cultivate with a tractor or to even rototill or mow while in an upright position. The trend is to do as much from the ground as possible. Al

You can shape your trees however you want. Just remember that if the first branches are six feet off the ground, that the fruit is all going to be above that, and your pruning even above that, so you're probably going to need a ladder to do thinning, pruning, picking, and spraying.

Low branches are great, but if you have rabbits, they can get trimmed back quite often. Even higher branches in the winter become low with a lot of snow.

I like the semi-dwarfs also. My preferance is to train for @ 6 feet minimum of ground clearance. The reasons for this are the dear browsing and having the ability to mow grass underneath on a zero turn rider mower. The view from above on a ladder is quite impresive! Besides, spray coverage from above on a ladder is better in my oppinion no matter what height your trees are. One must of course, consider physical ability as well.