To use the "My Watchlists" as an "action plan", when you have a list of stocks to buy or to sell, you need to sort them by order of your own ranking, priority, dates, the porfolio names against which you plan to buy or sell stocks, and other currently missing information that you may get from other sources such as next earnings due dates, etc. For this, you need to be able to add new empty columns with customizable column names so you can enter your own notes, and these new columns are sortable based on their contents.

Example:

Company, Symbol, ..., "My ranking", "Priority","Earnings date","Planned sell date", "Portfolio name",etc...

I have used other investment software packages that provide these features and they are extremely helpful to me, saving me tremendous time.