Water Rescue has huge potential really.
Would be great to have it added.
Divers would also be a great addition to the game.
I know the game is trying to be realistic in what it provides, however given that our emergency services have been majorly cut and had major changes I'd say sticking to realistic expectations for the game is not a good idea.
The game should be working to provide a good range of services and options avaliable for players to choose if they use them or not.
Personally I was working to build realistic services in Scotland. This has turned out to be impossible given how the game works. Realistically most of the Scottish Fire Stations are RDS or part time. Yes there are Wholetime stations in most major towns and cities but we are seeing a lot moving to 1 wholetime unit and remainder are either staffed during day and RDS at night or they have moved 2nd units fully to RDS. I have designed my full fire service to provide wholetime cover across all stations.
Then there is HART we have 3 full time HART bases in Scotland (there are a few part time units dotted around) that's it this given how calls generate is not enough, I've added in so far 8 total HART bases and even this is proving to be insufficient cover.
Police again these have been cut back in real life to the bare minimum for the game it is simply impossible to play with realistic police set up. I've built on both current and closed police sites and even the current police sites for some do not have any response units in real life. I have also stuck to keeping the same structure to all my police stations which when it comes to specialist units like Armed Response these are limited to a small hand full of units in real life. NPAS in Scotland is 1 helicopter in real life in game though I've got 6 and still need more.
I don't even cover all of Scotland, I cover Central Belt, Fife, Dundee, Aberdeen and Moray coast is my main area I have islands set ups too.
So although I play realistic locations that is as far as realism can practically go in the game just now. So addition of rare units only used by a handful of services would not really cause an issue if you want to add them then add them if you don't want them don't add them.
Bit like CC, HART and NPAS they can all be added and even turned off.
I have my HEMS off all the time.