To extend the stored log periods, you just need to adjust the server's cleanup settings.
Tools> Server options > Server Maintenance > Cleanup Settings
As for the client\scanner settings, That's one of the toughest things to get right. No two institutions have the same needs. Some may be perfectly fine with the default settings while others, like myself, have data that needs extra protection, we also have numerous exceptions we need the scanner to skip.
With an AV offering such diverse options as ESET does, it becomes necessary to pre-test any changes before making the config live. So i recommend doing that before each settings release.
I would start by enabling PUP protection, it's worth the hassle for us, but it may not be for others.