A simply seperation tool used in real life which would be amazing to have available for the approach contoller. This could be a standard message which gives 2 commands in one, most or all major airports around the world use this to maintain a seperation between airplanes when in final approach and landing.
180 knots till 10NM, 160 knots till 5NM.
When passing the 5NM distance you then reduce to your landing speed.
If you read this as pilot on the expert server, you can start using this already yourself without atc instructions.