There are two sets of plots that probably could be better. The first is the histogram. The auto limits is causing its x-axis to start at -2 instead of zero. I think this is fixed in master, but it might be good to have the autoscaling be tight (there are a variety of ways to do this). Second, the code for the very last plot seems overly complicated. I am pretty sure you don't need to be shifting the bars yourself anymore. I know it used to be required, but I am pretty sure we fixed that, I think. (if not, we really should fix it).