I have a few more random suggestions
1. SCUBA Diving. I would like to see a dive class created for fire and/or police. Dive expansion for Police and/or use the water rescue expansion for fire. boat requires trained personnel either swift water rescue or dive. Along with missions using dive team like vehicle recovery, search, evidence recovery, etc.
2. EMD (Emergency Medical Dispatch) upgrade for dispatch centers. When EMD upgrade is purchased with in game currency (credits not coins), patients timer for treatment/transport begins to reduce a little amount prior to units arrival on scene. As EMD trained dispatchers provide first aid instructions over the phone prior to EMS arrival in real life. This of course only working for missions that start with patients not missions that spawn patients after first units arrival or missions that upgrade with patients.
3. Again (because I cant stress this one enough) patrol routes that generate missions instead of all police missions only generating around the station. And new missions such as BOLO (Be on the look out for) spotted, routine traffic stop. Fleeing traffic stop, Pursuit, Amber Alerts, disabled vehicle, driver needing medical assistance, etc.
I really love the game but there is still so much more that could be added to make it better. I hope that these forums are actually viewed and considered by the people who can make these improvements happen.