As the title says, I'm wondering if it's possible to make a melee shapechanging-based Wizard that's combat-viable (i.e. able to contribute meaningfully to combat, in a non-optimizing group). Not trying to out-perform a Druid or anything like that, just wondering if it's possible--Natural Attacks should make up for the Wizard's lack of iterative attacks, but I'm not sure if it's possible to make up for the low BAB.
If you can keep close to a MED BAB with multiclassing and have multiple natural attacks it should be possible. The main issue in PFRPG is the MAD in these cases. As a caster you want your casting stat relatively high to have access to all your possible spell levels. As a melee character you want high STR and CON as well as DEX (not relying on armor being a shapeshifter). That means 3 stats to focus on, if not 4. A low point buy is going to have problems with that.
There was a thread awhile ago that pretty much asked the same thing, how to make a polymorph specialized arcane caster that 'works' might want to find it and dig through for any 'gems' it might have on the subject.