I think that is how I would do it also, except 4 and 5 are really one and the same. Just cut off 2 and 3, 1 is attached to 2 so if you cut off 2, you have also gotten rid of 3. When they have begun to grow, tape or tie the whole trunk to a stake and it will grow straighter.
If you just planted it, you can prune this way and then just let everything gropw this year. If it was planted last year, prune the same, but try to keep new growth going upright.