canon G1X or panasonic G3 ?
You'll get moderate shallow DOF with a u4/3, even with a superfast lens.
You'll get moderate shallow DOF with the G1x, owing to its larger sensor, but the lens is somewhat slow at anything but wide.
Both are capable of shallow DOF, depending on your understanding of physics and how you compose. Also, bokeh isn't simply quantitative. It's qualitative. You want the right kind and you don't want to compose around the bokeh. Bokeh is overrated and should be an accent to the composition, not be the composition.
Also, look for something that might be an APSc mirrorless. Even try out a Pentax K-01, if you can put up with the size. Put a fast lens on there, like an FA50, and you'll do great.
The biggest thing you can do to improve image quality on nearly anything is to evaluate where your skills at and learn how to use the functions of the cam and not leave everything in auto.
Get too much cam without knowing how to use it and you'll end up likely getting worse results.
Get an idea from this thread: