I was practicing Syndra tonight and happened across a 1200+ win Xerath. It didn't end well. Couldn't hit my fricking stun to save my life. Gonna have to give him a go tomorrow when he goes on sale.
Currently, as I near 30 and getting ready to play some ranked games:
Top: Renekton, Elise then Darius/Rumble/Zac/Wukong - first two are my prime choice
Mid: Orianna, Corki then Fizz or Swain
Jungle: Nasus, Zac, Elise, Yi
Some jungle characters I have, that I do like playing but don't have practice on is J4, Naut, Malphite and Volibear.
Then I have the normal run of support characters that I'm decent on. I really love Maokai support with an aggressive adc. With Caitlyn and my bombs, the poke is funny.