Probably more often than not, I use the dual cursors to determine the frequency of periodic events, especially when the time period is short. However, the frequency is not shown, only the period.
My feature request is to default to delta-t, but have a hotkey to toggle between delta-t and frequency. This might cause issues for you, though, since you have the same statistics for the window, where a frequency probably doesn’t make sense. An acceptable alternative would be to only apply the hotkey to the value between the flags (which, BTW, I would REALLY like to see moved upwards a bit including both flag values - so that they are never over the time axis labels, and they would also be easier to read when the flags are close together).
FYI, just downloaded 0.9.11. It seems like the dark blue ‘time window’, for lack of a better description, could be not so thick, and also not have the 'Time (seconds) label within it. If made thinner, there would be more room to accommodate the elevated cursor text.