Plus shapeshifting and the fact that you can wear up to medium armor (if you take Battle Caster) and you get a fairly adaptable character who can also survive a melee pretty well. But I would imagine it could be good for a more offensive build, with your spontaneously cast-blasts backed up by druidic buffing and blasting spells.

Warlock/Druid: I admit I am not heavily familiar with the Warlock, and know it has some issues. But that's what magic items/buffs are for if you in fact create a item-creator (I don't know what creation options are available on the server you play on), you could probably make an awesome character who can make his own potent protective items (bracers, rings, etc.) that would make the lack of armor availability less of an issue. For some of your build options, yes, you will have to give up armor. Understand that some sacrifices will need to be made.

There's a couple ways you could go about doing this, depending on what you want, such as being a blaster type or buffer type, or say, you primarily want to be a blaster-mage but want a few healing spells to keep you healthy, etc.

Nwn2 wizard spell list