After using the declarative plotting interface in some examples, here are some suggestions for improvements to the declarative plotting interface. I'd propose that this is a 'living issue' and contributed to by any and all with individual issues/PRs being raised as this wish list is addressed.

• Currently any out of order execution (common in the notebooks) causes errors. I don't know if we can fix that due to the way the internals work, but at least documenting this and setting best practices of all declarative plotting calls in a single notebook cell might be best.
• Layout of plots does not work as one might initially expect. Currently we set the layout attribute on a panel with a tuple of the location as in matplotlib. (1, 2, 2) While that behavior is fine, when adding panels to the panel container we just pass a simple list. It would be desirable to have the capability to not set the layout attribute and determine the layout by passing a list of lists. For example to layout a 2x2 figure it would be pc.panels = [[p1, p2], [p3, p4]].
• Currently if you want the same contour plot on two different panels, you have to create the contour plots twice as they cannot be reused. This seems like a pitfall as it requires duplication of code and cycles. I can see many scenarios like wanting contoured heights on two different panels in the same panel container.
• Adding an XY plot would be good so panels with time, temperature graphs, etc could be added.
• When Add function to find local extrema and plot separately #1689 is solved, add an attribute that ties into the max/min plotting (akin to the GEMPAK HILO parameter).