Only thing that bothers me is that Augment Summoning doesn't help all our Elementals equally. Air and Fire Elementals use Weapon Finesse, so the boost to Strength, while increasing their damage, does not increase their attack bonus. And, as written (though it may take some convincing of your DM), Augment Elemental would boost the damage done by the special abilities of Storm Elementals (being a flat +2 enhancement bonus to 'damage rolls'), and possibly even Orglashes and Thomils. I find it has the advantage of not needing any real prerequisites. You can grab Animal-based Augment Summoning from the Initiate of Malar, then when you shift to summoning Elementals at about 9th level, exchange it through retraining for Augment Elemental.
I did not know PHB2 changed the Dire Eagle. Makes sense, it outstrips every other animal companion at that level.
Finally, there is an interesting Magic Item that I didn't see in the guide. The Skin of Kaletor from Dragon 324. It's 12k, takes up your Back slot (Not shoulders, so you can still use the Mantle of the Beast, which is important), and gives you a -6 penalty on Charisma based and Wild Empathy checks. In exchange, it gives you a +4 bonus to your effective druid level for Wild Shape. Combined with the Wild Shape Amulet and Armor of the Beast, you can Wild Shape as a druid 9 levels higher than normal. With these three (technically 5, since the Armor of the Beast is a set), you'd be able to Wild Shape at 15th level into anything with 24 hit dice or less, of up to Gargantuan Size (Megadolon Empowerment spell is 8th level, so 15th level to cast), of the Animal, Plant, or Elemental types. Elder Elementals just so happen to have 24 hit dice.
As I said, I just got back into 3.5, so if I find anything of interest while combing my old books, I'll post it here.