Not OP, but I've also been look for a way to leave ggplot2 behind and make the jump to 100% python for data analysis. These look neat.
Seaborn - http://web.stanford.edu/~mwaskom/software/seaborn/
Blaze - http://blaze.pydata.org/docs/v_0_6_5/index.html
Bokeh - http://bokeh.pydata.org/