Don't get me wrong, the GH4 is awesome for video. If the G7 is anything like the GH4 (and by all accounts it seems like it is at least as good) you will love it for the quality of the video it produces.
Although the GH4 was marketed as a dual-purpose camera, the use cases for video and stills are very different. At the next event where I have to shoot both stills and video, I will carry two bodies: The K3 for stills, and the GH4 for video. After all, for many of my past events where I only shot stills, I often carried two bodies, and I am just an amateur photographer. There are even more reasons to carry two bodies when shooting both stills and video. In addition to the different exposure/focus settings, all the peripheral gear is also different. For example, many events are dark and you instantly will need a flash on your stills camera, and an LED video light for video, in addition to your audio/mic. One takes a ballhead, the other takes a monopod with a fluid head. On and on. (Not saying that you personally have to carry two bodies; it depends on what you are doing.)
Also, you will find that the way you compose your shots and move around the room is different.
My main point is, the fact that some stills cameras can take video, is a red herring. The experience of shooting stills and video is different. The important thing is to use the best tool for the job, and that might or might not be a large-sensor camera.
Good luck! I wish there were a Panasonic forum as good as Pentax Forums, let me know if you find one.
Last edited by Tanzer; 08-19-2015 at 02:54 PM.