Double Draconic Aura is probably a good feet. I'd also trade out an Aura known for Least Invocation -Endure Exposure. So the little guy can breathe on everything with no worries of friendly fire.
Rather than trading an aura known, I could take a 1 level dip into DFA for that Least Invocation along with a weaker but spammable breath weapon... add Practiced Invoker and it'll be bumped up to a spammable 3d6 breath weapon.
So...
Pseudodragon:2(+3)/Fighter:2/PsyWarrior:2/DFA:1/Dragon Shaman:9+
Feats: Double Draconic Aura, Practiced Invoker, Entangling Exhalation, Exhaled Barrier, Exhaled Immunity, [+6 More Feats]
As for adding level of Soul Eater... I don't really feel the class fits... I do however like the Spellfire Wielder feat, and it seems appropriate that my familiar might possess some ability for redirecting spells, since I myself am playing as a spellthief (mostly Mystic Theurge[Wizard/Archivist], but I still play as a spellthief since thats what I started out as)...
So I'll add Spellfire Wielder as a maybe. It's worth noting right now... that my DM is only allowing me to add up to 2 1st Lv only feats (via the 2 flaws).. so if I include Spellfire Wielder, then that will take up 1 of those 2.
Edit: I'm pretty sure I actually won't need Endure Exposure or Exhaled Immunity though... since I'm taking Gold Dragon as her totem, and the entire party is immune to fire damage... however, the invocation might still be useful... of I could take Magic Insight instead of Endure Exposure, and use Exhaled Immunity to grant any temporary allies we may have immunity to her breath... I'm honestly leaning more towards that, since having a free unlimited use ability to identify magic items would aid the party greatly... we've been paying for identifies 90% of the time since none of our casters want to become intoxicated for a whole day while they identify stuff...