It seems to me that it's always been the servers that have unoriginal gamemodes, low quality/reused builds and poor moderation that are always dominating the server list. I get it that some people like playing the same old gamemodes for years on end but I wish there was always something else to do other than Jail RPs, Knife TDMs, Falling platforms, City RPs, "realistic" TDMs, ZAPTs, Trench TDMs and Infinite mining. These type of servers are always the same old thing and I don't see what's so great about them anymore.
And for goodness sake, people. Stop using the stupid votekick mod. Its a horrible way to moderate your server and chances are everyone who's hosted with this has gotten a drama on their server before. I can't believe I have to even say this but it's still a big problem.
There are a lot of original gamemode ideas out there that are just as interesting but I rarely ever see them at the top of the player list. Starship creeper survivals are a great example.
I should make a little chart listing different server gamemodes based on which are best.