[D&D 3.5] Input appreciated: Fighter / Wizard / Abjurant Champion Gish

[Myrmex]

Is there any reason you're going abjurer?

I would go focused specialist transmuter, banning evocation, enchantment, and necromancy. Transmutation buffs are amazing, and illusions are good for getting percent miss chance.

Also, you may want to take some points out of strength and add it to dex, since getting your AC up without armor would be helpful.

However, githcraft mithril twilight fullplate with thistledown padding and a level in spellsword puts your ASF for armor at 0%. Dex bonus caps at +3, though.

As for polymorphing, if you are going to be doing a lot of it, I recommend moving more of your phsyical stats to mental stats. A good shape to be in is wartroll- they get a stun on their attacks as an Ex ability. I would downgrade str to 13 and max con, actually, seeing as how it's only 12. For being on the frontline, 12 con is quite squishy.

What level are you starting at?
Can you use ToB? A first level of crusader or Warblade, if you're not too attached to the bonus feat, might get you more than a level of fighter, in terms of maneuvers/stances. You'd have to look at it and decide for yourself, though.

If you are really going for broke, wraithstrike resolves your attacks as touch attacks for a round, while scintillating scales will turn your sizeable natural armor bonus from polymorping into a deflection bonus.

If you are going to gain levels beyond 13, I would recommend going into eldritch knight. You'll lose two caster levels, but that can be made up with practiced spell caster.

Weapon focus, specialization, and mastery aren't awesome, especially considering that you're going to be polymorphing. Multiattack and improved multiattack may be better, as they will give you basically +5 to all your wings/tails/claws as opposed to +1 to hit with a greatsword.

Since you'll be using arcane strike, getting extra natural attacks will be worth it. Those spells that grow you extra tentacles, in conjunction with multiattack, will further increase damage output. Dragons with tentacles. Ewwww.