User blog comment:B214/Volume 22 spoilers/@comment-64.237.231.92-20160722012904/@comment-1359322-20160722120129

Vali is already close to Heavenly Dragon level. The only thing he has to do is to increase his stamina, reduce the energy consumption and further increase his power output. He'll naturally be able to surpass the Heavenly Dragon-class. He did beat Azi who's supposedly Heavenly Dragon-class.