I haven't seen much talk of using the over archetypes over than loredrake for optimizing potential. Flame of the Forge, Lightkeeper, Passion's Flame, Stalking Wyrm, and Wyrm of War all seems like okay choices for "dragons" that won't be using much spell casting.
If you abuse aging, archetypes cost more than they give.
For example, the well loved Loredrake to a Steel Dragon is +2 to Sorcerer Levels.
To the guy abusing aging, it's loss of every Cleric spell ever and they probably have +6 Sorcerer Levels after a spell or two anyway.
Wyrm At War would be amazing for gishes though. Feral Death Blow at level 10 or so? Yes please. Also, Dispassionate Watcher deserves a mention. A single level in it swaps your arcane based spellcasting gained from aging to divine spellcasting progression based directly off your divine class. So a Steel could trade away it's Cleric spells for the ability to learn maneuvers, then go Cleric 1 for divine spells and then to say Eldritch Theurge. On aging it would faster progress it's Cleric casting rather than Sorcerer, the primary aim is age buffs to make up CL loss, you get divine and arcane and martial, and the ability to use DDM(Persist). Run the whole thing off Ur-Priest instead and it just gets crazy.