If you are really into ATC control, then look at acquiring Radar
Contact. The latest version will work with both FS2K2 and FS2K4 and
requires the latest version of FSUIPC but should register itself with
that utility for the few services it requires.

Either before you intialize the flight or during any appropriate phase
you can request departure and arrival runways, or request to follow an
approach procedure (IAP) as published for a particulat entry. You can
use a flight planner of your choice exporting in the MS flight plan
format so SIDS and STARS can be used by entering the waypoints.

You can also let RC choose the arrival based on wind, runway facilities,
etc.

The latest version now recognizes AI enroute and will call traffic
target advisories (but not control AI). On final, it will recognise AI
entering the runway and order a go-around.

Be prepared to digest a fairly large manual in .pdf format. In my case I
had it printed and bound at a local shop.

You can find their support forum on Avsim.