Why don't you just wrap the dock after bathing so the hair dries flat? I think a neat natural tail could be just fine, although I show at Arab breed shows or dressage where a natural tail is either common or required!
Braiding is a good skill to learn, for sure, but that's just my two cents!
ETA... obviously, there are special wraps for this purpose! You don't want to harm your horse by cutting off circulation at the dock. :)