Unless you've been under a rock, you've heard about GTA V RP (roleplay).
The rules are as clear as real life, pick a role and run your in-game life accordingly. There are police officers, hotel employees and pretty much anything you can think of.
Want faster paced gameplay, play a police officer and sniff out the criminals. But be careful, ignoring the server rules can get you kicked from the server.
Modifications to the game have added much diversity and endless content to the game. The question is, does this interfere with developer DLC? If you can code something into the game, why would anyone pay for added DLC? This remains yet to be seen.
Starting a GTA roleplay server is a bit more complicated then a few clicks, after talking to long time GTA RP player + Alt Partner Akkadiaan, this seems to be the case.
Constant developer support is needed to run some of the largest servers out there, such as ones played by Shroud, XQC and more.
Have you tried GTA RP?