With the ELO changes coming up, it's hard to say for certain. IMO, there are no bad clans (though certainly there are bad clan pairings), so just go with what you are most comfortable playing with.
I would recommend using at least one clan with an attack bonus unless you are playing Nightmare (...or Freaks). Use this as a support clan if you are strongest elsewhere.
Pussycats will rule ELO
Fang Pi Clang will be a very good partner w/ them
Pussycats/Fang Pi Clang
Charlie 4*/Baby Q
Yayoi
Ella
Feelyn
Kerozinn Cr
Marlysa Cr
Windy Mor
Xia Leming