On a totally unrelated front, I had been giving thought to the 3rd level spell to take when I reach level 6...
Three options I had finalized on are fireball, haste, or protection from energy.
Fireball - ranged nuke. My cold breath would do 6d6 as well, which would be the same, but the breath is a 30' cone, rather than an aimed shot with burst radius.
Haste - all around good party buff - extra attacks, speed, ac, etc, etc.
Protection from Energy - to keep me alive in battles with either casters or creatures with breath weapons.
At this point, I am leaning to Protection from Energy, as the cold breath is a good damage dealing option to fall back on, and I have very few hp's -- any more in-game references to Tiamat, and my character will definitely be getting this. Dragons + d4 hit die = dead PC.
So, 1st = Pro/Energy, 2nd = Haste, 3rd = Fireball at this point.