Put some time in (top two ranks as of two days ago, SY and LHR), the biggest problem is the altitude the inbounds start at; sure continue the pop-up nature to spice it up but have them come in a 50, 60, and 70 not at what appear to be strange levels sometimes appearing in clusters already in conflict. Would be good if you could multi-task, ie give two instructions at once like tracking, heading or levels etc. They also climb and descend like 'dogs'.
Also nice to see the strip 'higlighted' when you have the callsign (by clicking the label) in the task window, so you can read the information, they get lost when there are similar callsigns and numbers.
If only the 'real world' we as easy as this...