I don't know if this is even possible, but I think it would be neat for certain special rooms to have a sound byte attached to them that you could toggle on/off at your leisure when playing on the browser.
Something like @room-sounds on/off
So, for instance, when you walk into the levs maybe you hear a muffled voice calling out stations, or even the swoosh of an incoming train when it enters/exits.
Or when you walk into a club like Carnal Desires or KMB, you hear a brief thumping of club beats.
Thinking it wouldn't be something more than 1 or 2 seconds long. These days I'm sure AI could whip up sound bytes like nobody's business.