Quoted By:
Onix/Steelix: Switch to Rock/Dragon and Steel/Dragon. The look Draconic, use Dragon moves, and Ground/Rock is oversaturated.
Flygon: Do I really have to say it?
The Birbs: Make them pure Flying. Besides the fact we have no real mono-flying types anyway, it makes no sense to have them part normal without a pure flying type for them to be more "normal" in relation to.