For me, the annualized ROI on an investments current holdings, coupled with the Gain are the two most important numbers for making a sell decision. (i.e. has there been an exceptional run and how much would the profit be).
I typically use the Share Price graph with x-axis at the TRN setting, the Value and OOP Cost fields in the legend (permitting a mental calculation of GAIN), along with the top-of-graph ROI. This works alright for investments that have been continually alive (have never been sold completely) but does not work for current holdings in investments that have been sold off and purchased again. IOW, I want the "Gain - current" and "ROI - current", not historical. And all on one graph, please.

The Gain graph can be helpful, and C and H can be toggled. But there remains the ROI problem.
1) Perhaps, a toggled GAIN could be included as a field in the Share Price graph legend? And in the Cost - Price graph? (In fact, why not allow ALL legend fields in every type of graph??)
2) Could the (annualized) ROI-C also be displayed somewhere? It sure would be handy.