I'm not a fan of CityRp's and have only ever enjoyed 2, although 1 of them was mine, and it never started. I only enjoyed it because I made a tunnel with a ramped cieling with a right-angle in it. I'm so proud. :')
The other CityRp was Real Neo's, but I believe that was running on an edit of someone elses. It went realy well, actually.
Proper Roleplay wise, I have only ever, to be honest, enjoyed Roleplays on 3 different servers.
1 of them was on Stone Brick's server, although his were defintely more on the lines of an RPG.
The second was, again, on mine, but they're good because of the people who join in and help, and the great ideas that keep rolling in.
The final one, and the one that has allways had the best (Although some have occasionally been lacking) is Liquid's server.
Although I haven't been able to connect to Liquid's server for some time now, and he's graciously spared Host capabilities to allow me to host for him so we can both enjoy it, I allways enjoyed Liquid's Rp's the most.
Absolutely brilliant range of roleplays. There's been Medieval, Medieval with slight twists (Say Time-Travelling?), Space roleplays, Apocolypse roleplays, City roleplays (Not CityRp, an actual roleplay), Business style roleplays, and loads more.
The best part is that each roleplay usually only lasts about a fortnight or so, before some other brilliant idea rolls in. But, we can get a lot of fun and different roleplays that end up wrapping their own history around the build in that little time.
Even if it is self-advertising or advertising for a close friend, I suggest that you absolutely join Liquid's Server if ever he is doing an Rp, or join "Sir Dooble's: Immersion" if ever there is an Rp on. You'll most likely find the same crowd and the same brilliant atmoshpere at both of the servers, and if you pick your timing right, you can drop right into a fantastic roleplay that varies from the bizarre to the unusually fun for having next to nothing there.