Nail said:
A wizard that marches into melee combat as an Annis deserves what he gets. The form doesn't give nearly enough AC or hp to survive as a front-line fighter. And the wizard's attack roll will still suck. Two claws and a bite for 1d6 plus strength? Not enough.
A 7th level wizard can make a fine melee type character if the design is smart. A typical wizard might want to use polymorph for transportation, healing or as a last resort, but a wizard designed for melee combat can still take great advantage out of the form.
I played a 3.0 dwarven battle-wizard that held his own with the PC barbarian in melee combat. Things have changed a bit since 3.0, but not so much that the design would not work. Polymorph is a key component of that build, providing multiple attacks, great natural armor, reach, special attacks, etc ... Around 7th level, he used the annis form in combat. He did deserve what he got. What he got was to kick butt. By itself, an Annis form doesn't give enough to go in the front lines. But combined with
shield, blur, blink, improved invisibility, mage armor or a host of other spells, it is just fine. Most 7th level fighters with +2 two handed weapons deal an average of about 25 damage versus an AC 21 foe in a round. A spelled up wizard in Annis form will deliver an average of about 43 damage in a round. Even more if there is a druid in the party. plus, the Annis wizard can have an AC in the high 20s while the foes have miss chances against him.
It may not be your cup of tea, but don't assume that a melee wizard won't work. My own experience shows that it does work ... and it works very well.