Any good mmo's with decent playerbase? (Private servers)

Looking for good mmo's with a decent playerbase. Mainly some private servers that arent too op.

if you can pay, u should try Archeage Unchained (its a reworked Buy2Play version of Archeage (a free2play (more p2win)) with no pay2win things).

Its amazing for 25$. there is lot of people in EU and US