Honestly other than how the server run and how well I can play on it, I look for no drama. That's how we run the server I'm on right now. A lot of servers have a ton of drama and really sometimes there is no way to avoid drama but for the most part if you have good people who just want to play the game and don't have any other motives the server turns out fantastic.
But everyone looks for something different in servers. There is really no way to cater to everyone unless you run multiple servers. Which is rough. So stick with how you like to admin and the people who like it will stay. Its a combination of finding good people and being a good admin
don't worry about coming and going. That's just how it is. You'll get people who are dedicated and who will stay eventually.