This is caused by the introduction of Old English bantams to form the bantam gene by Perrin Johnson in the 1930s when he started Red bantams. Like the white leghorn bantams they also, had white old English blood to get the bantam gene into the large fowl white leghorns. If you go to any show all the top white leghorn bantams have pointed down wings. There for, it would take maybe 10 years of breeding pressure to try to get the wing carriage level and in my opine it would be third on your list for right now. The sizes of our Red bantams on the whole are mixed.
Some strains are larger than others are.
There is no Poultry show or judge that weighs bantams so its up to the judge to nock down a Red bantam for size. There for it is important to have Red Bantams that are nice and small and that would be my second choice of importance. The top lines that we see today are getting worse and worse each year. Judges keep awarding the big wins to these kinds of bantams and in many strains they have become a fixed trait. One person told me that a excellent breeder told him if he does not bring the Plymouth Rock reds to the show he will get beat.