If you are interested in making a Wandering Isle stayer for big community, here you can have a list of realms with big Wandering Isle stayer communities.
Remember, that being in a populated realm has it's pros and cons.
+ More people to do stuff with
+ less boredom
+ Highly developed economy
- Limited amount of herbs / ores, thus slower levelling.
Overall, it's better to go to populated realms simply because alone you will level fast but will become bored extremely fast.
Europe (EU) realmsEdit
Magtheridon - biggest EU community of stayers. A few playing actively + some others logging in occasionally.
United States (US) realmsEdit
Mannoroth - US realm with (currently) highest level stayer - Doubleagent.
Darrowmere - Once biggest US realm now dead.