[Markus1337]

What kind of server/gamemode would yield most success if it was started today?

[SickAttack]

None, because everything has a start. The server would have to work itself upwards.

[CalvinC]

They'll probably all yield about the same success, depends on your uniqueness and features to get players to stay though.

[Ironboy]

As said above its not a matter of what gamemode you use but the effort that you put forward into it.
Take a look at these threads
http://forum.sa-mp.com/showthread.ph...cessful+server
http://forum.sa-mp.com/showthread.ph...cessful+server