In Germany, drivers of long-distance trains receive the Zp9 (a signal that tells them they’re clear to depart) on a mobile device along with a sound (Users of the ICE 1 Enhancement pack might already know it). My suggestion is to basically add this to the existing ICE and IC trains in the sim. I think this is a tiny feature which would increase immersion a lot. (I hardly found any information on this so it is also based on personal knowledge which might not exactly be accurate, sorry for that in advance)
