No objections here!
What class is your character again, Sparky? Cuz...a roundabout way to have a riding dragon is this:
1) Have an arcane class, or Multiclass into one.
2) Take Arcane Familiar feat. Select a draconic type familiar (there are several).
3) If you do not have Ritual Casting...take it. Then buy the Familiar Mount ritual.
Boom. Done. Costs some money and takes some time, but you can now turn your shoulder-dragon into a riding dragon whenever you wish. And it only cost 1 to 3 feats depending on what you got from your class!
...you know, Su could totally do that too.
HMMM...
Edit - Oh, and you have to be high enough level to cast the ritual, of course. But I think level 8 is high enough.