So, Chris is out for the day, but I had a brief chat and said he is okay with us doing a little modding on this. That being the case, some information followed by a fix to the disease problem.
Your SBR install folder is probably located somewhere similar to: C:\Program Files\Steam\steamapps\common\Stars Beyond Reach
The game actually reads some of the parameters for things from .xlxs (files). That means we can mod those files and it will affect the game. You have to restart the game, but any changes made to the files will affect both new and current games. If you switch back or replace the modded files it will likewise change any loaded saves.
The data files are in: C:\Program Files\Steam\steamapps\common\Stars Beyond Reach\RuntimeData\Configuration
The files should be straightforward. I haven't done a comprehensive listing of the fields, but it isn't bad. There are other fields that are not listed in the files, but I don't have that list either.
So, how to fix diseases. The solution is the CDC (Disease Control building), available from Epidemiology.
CDC does work. However, the impact is not very big and suffers from some other issues.
My understanding of how disease works is as follows:
Each disease has a Severity from 1 to 100 (100 is the worst).
Each CDC contributes 1 vaccine point.
Each CDC requires 400? people to run it.
When a disease hits, you will suffer 5% or so deaths each turn it seems (per disease?).
To "cure" a disease you need to accumulative (what seems to be) a number of vaccine points equal to the disease Severity.
However, your CDC will become unmanned very quickly, and due to deaths and the points don't accumulate. The average disease has a 50 severity, so if I'm correct it would take 50 turns to cure with a single CDC. The death rate from disease is currently too high to manage it. However Chris is changing it all, so it doesn't matter.
I have a save where I get AlveolarDecay on turn 165 every time. I am able to fight it off by turn 167 using 11 CDCs. The Severity of AlveolarDecay is 22. I probably could test this by building 22 CDCs and seeing if I get over it in one turn, but Chris has direct access so not much point. I provide this so others can have an idea of how to deal with it.
Installation Instructions
In the attached zip file are the original files to be kept as backups and the new modded files that should help with the disease problem.
Copy them into your data file directory, overwriting the files there now. If you update the game, it will delete the files.
The fix:
Step 1. Reduce the cost of Epidemiology to something reasonable (600).
Step 2. Reduce the cost, energy requirement, and employment requirements (10000,10000,10).
Step 3. Reduce the disease severity by a factor of 10.
Step 4. Reduce Stock Exchange and International Banks from 60 times as much crime as a bank to just 2 times.
You should still get diseases. They should still be annoying. They should not destroy you anymore.
Pollution is also kept more in check. Build all pollution buildings to the right of everything else, put hazmats to the right of the pollution buildings, and keep a few scattered throughout the rest of your town. Note most advanced buildings produce smog.
Crime is also kept in check. Build police stations to cover EVERY building you have. Build 1-3 police stations around your Banks & Stock Exchanges.