When you look at the left panel, select Transactions, and then pick a Mission, there's room for one more button - PLOT COURSE. This would be wonderful! Insert it right before "Open Galaxy Map", since this is why I click that button in the first place, to plot a course.
ps - Not everyone is on a platform that opens the galaxy map instantly (cough console cough).
ps - Not everyone is on a platform that opens the galaxy map instantly (cough console cough).