I think Ultima Online had the best implemention as far as limiting players goes.
They had it set up so that for the first hour of gameplay everyday, you gained skills/stats faster than during subsequent hours of play. People could grind all day long, but that first hour (power hour as they called it) made it just a tad more accessible to newcomers and casual players. Granted the game still required huge amounts of time to get anywhere, but it was something... I guess.
Demon's Souls Official Thread | Currently playing: Left 4 Dead 2, LittleBigPlanet 2, Magicka







