I gather Draconians would probably fracture somewhat like lots of races would do in 4e. For instance, a Baaz Grunt may be a level 3 minion while a Baaz Champion may be a level 7 elite soldier. I'd rate the "base levels" of each type as 2 for Baaz, 4 for Kapak, 6 for Bozak, 8 for Sivak, and 10 for Aurak. Some special individuals may be 2 or 4 levels higher.
Certain computer games featured very high-level play in the Dragonlance world - and these had "enchanted" draconians of each type that I'd rate as 10 levels higher (kind of like "gain 1 tier and go on" monsters).