I actually have a clause in my contract that states that we deliver "edited video as final product - not raw files." I've just had a couple of clients that question this, and when I explain further I tell them I do not recommend getting the RAW footage. If they insist I mention I would be willing to sell everything (sometimes up to 350 or 400 GB) for about $1000.00. No one has bought it yet, and honestly, that's because I really don't want to sell it or give it away. Why? I think this is one of those little things that can hurt the professional image of my business. The reasoning behind "getting the raw footage" is that clients think they will get more material than what they are getting from their edited videos. I think our packages are designed to deliver most of what is 'usable' or 'watchable.' They want to see more video? They can upgrade to a more complete package. The most popular package, however, already has a couple of documentary edits (ceremony, special dances, toasts), a feature film, a highlights film, and any other part of the day that I can edit in documentary style (multi-cam edits for toasts, or first look, etc.). What is left after these edits is really just shaky footage or pieces that have no coherence.
Clients usually will ask for Raw footage if you are shooting documentary style all throughout the day, mainly for coverage (instead of moments). Selling it or giving it may work for some, but not so much for those shooting for shorter edits. What people expect when they ask for raw footage is a very long video, not hundreds of small clips.
I think it's in the right of the wedding videographer or cinematographer to refuse to give the RAW footage away and only deliver edits that will reflect the production value that he or she sells. The same way as photographers do not give the thousands of raw photos they take and make a selection before delivery.
You may already know but it really depends a lot on what you are planning shoot or the look you are trying to achieve. I personally love fast lenses, so I wouldn't buy an f 3.5-5.6. Especially for the GH3 since we all know it's not so good at low light. If you already have tons of light, or are planning to shoot in day only, well, then that's not a problem.
My main cameras are currently a couple of GH3s and the one thing I really like about these is that you can pretty much fit almost everything with an adapter. At least the most popular brands... but also old lenses. Get primes, they're the best. I really recommend any Rokinon for its glass and build. You don't "have" to spend extra to get cine lenses, as even the normal ones are great. My favorite and most versatile is a Rokinon 35 1.4 that I found pretty cheap on eBay, it had a Pentax mount but with and adapter it's great on the GH3.
While optical image stabilization is great, I would suggest not to limit yourself to lenses with stabilization and rather spend on some stabilization tools (at least a monopod, shoulder mount, blablabla...). You can find really affordable stuff that will make a big difference in the outcome.