Personally I think Dragons Breath is fine the way it is and I love the solar flare concept. I hate the idea that a rocket launcher has to have tracking in order to be exotic.
With that said, a lot of people think DB needs a buff so I think giving it an Ignite perk instead of simple tracking or early detonation (which has already been done) would do the trick. Rounds fired from DB Ignite enemies and leave a solar flare upon detonation. Thoughts?