The idea is to make world act like a treadmill belt.
New areas would be periodically generated on west side and at the same time on the eastern side same amount of land would gradually sink into ocean and be subsequently removed from the world. New players would be spawned in new areas. The world shape would be rectangular with E-W side longer. The time from generating to fully sinking should be around one year. Some warning signs should be provided to let players know it is time to escape.
That would not help with high qualities but will allow for some fresh land as well as force permanent struggle for new resources.
*The direction of migration east-to-west was chosen because of dominant migration direction in recent 2k years.