There are some interesting "Creative Filters", some that I found it fun are the monotone, dramatic monotone, impressive art, bleach bypass! All taken with Panasonic 7-14 F4 lens.
Shot on a wet and gloomy day, the "impressive art" creative filter adds much punch to a boring scene
Update on low light focusing. It does hunt in very low light situations. For example, trying to focus on the eye at ISO3200, f/1.7 and 1/10s it would hunt for a while before focusing. I think, we still can't compare that to the D4 or D800.
Sorry for the late reply. Art filter cannot be applied after the pic is taken. Not sure if it can be applied using the panasonic software though. Will check that out over the weekend