to start off, I have a gh2 and a few lenses for it. I really think you would be liming yourself if you get the tokina 11-16 as your only lens. Personally I would look for a mid wide-standard zoom, a fast tele prime, and a something ultrawide/fisheye if you still have money. Craigslist can have amazing deals. Also, check this out, whole collection of lenses people have tried on the gh2 and how they work.
Also, I knwo you said you had all the accessories, but do you have a lot of good memory cards?I shoot with one of the highest quality hacks, and there are only a few cards that keep up well. If you shoot with a lower bitrate hack (which will still give great quality), it is less of an issue, but you will still need lots of fast cards. 32gb is less than 30min for me. Lastly, unless these will be well lit, stay away from b4 lenses. While they can be very fast, cheap and parfocal, you almost always have to use them in crop mode, and low light in crop mode is one of the gh2's weakest points. If you won't have to go above iso 800ish you can get away with it, and it may be possible at the right venue (also most of the lenses are f1.8), so if that is the case, go for it. Otherwise, stick to some of the others