Any chance we can get a hint on the dragon themed archetype? Off the top of my head I can really only think of:
Draconic Bloodline Sorcerer and Way of the Ascending Dragon Monk.
Both of which, while neat, I feel like would ultimately end up stepping on the toes of Draconic Incarnation/Dragonborn.
Red Dragon Disciple, which is kind of a weird one as it's got largely bonuses you'd want for a melee but requires bard or sorc levels.
As an aside, don't really look to 5e stuff for where archetype ideas are coming from, they're mostly derived from 3.5 prestige classes.