My reasons to ask for this: Aggregation API, Transform API and method-chaining-friendly Series/DataFrame.set_axis. The absence of these in pandas==0.18.1 introduced (of course minor, but) noticeable friction of transition from other Jupyter environments (most notably Kaggle) to Quantopian Research.
I very much understand that it may be pretty hard (if at all possible) to incorporate "latest versions of everything" that we keep requesting, but latest Zipline requires pandas<=0.22.0, so maybe.
Comments are welcome! :)