Eventually, we need to be able to:
Request a different runway for departure (including intersection departures)
Request a different final altitude (from a list of altitudes, not 5000 higher/lower, just ‘Request FL310’ is much more realistic) - this, in the menu, could be selectable by 0-FL99/FL100-FL199 etc, then FL310.
Request a further climb/descent if they have not climbed or descended you yet
Request a heading due to weather etc
Request direct tracking
Request holding (and then onwards clearance)
Request a particular approach type (ILS/RNAV/VOR/NDB/Visual Approach, etc)
This would make things much more realistic.
And PLEASE, support ICAO phraseology (the US does almost EVERYTHING differently in this world)