I did my dragon run with only noibats for the first gyms, then fill in underways with what I got. Axew from Mystery egg was important, he was the MVP of the run with Dragon dance. The first gyms was hardest, but the run got easier as it progressed, because of the sheer power of the dragons. Until Serra I only had 5x noibat/Noivern and 1x axew/evolved form