I would like to see trendlines become easier. I am surprised that trendlines for Klipfolio are not as easy as excel. I believe it should be as easy as a button click to pull information from an excel data source and drop in a trendline into your Klip, just like excel would do it.
The math function is not a very good option.
Also with this, I would like to see it act like Excel where it ignores cells that have #N/A in them.