As there will only be 300 players per server, and the game will have no npcs in the open world, the world will seem kinda dead. Take SAMP for example, there are servers up to a thousand players, even then the map isn't really that crowded, keep in mind that the map of San Andreas is only 14 square miles, while this will be around 80. Most people will probably be in one of the main cities in identity, which will lead to the other cities being pretty empty, and the wilderness etc being almost completely dead. What if you made some kind of crossrealm zones like in World of Warcraft, where zones that doesn't have many players on it gets merged together with players from other servers to make it more alive. Divide the map into several zones, each city being a zone on its own, small towns, mountain areas etc. Each zone will have a different number of player cap, a big city should have more players than a small town etc.