I don't know if you realize that there are limitations to hardware and the game itself that makes it very hard to have an unlimited amount of people online, and if it is possible in some sort of way it would be extremely expensive, and as a result the server would not be able to remain free.
Making a new server will take a load off the old one, and hopefully make the current one stable, as wish for.
For example 2 servers with 4k people is much less expensive and easier to maintain lag free than 1 server with 8k people.