There is quite a lot of options, depends on your enemies which is best. Kushina+Gaara combo is strong but slow, if you want to kill faster Killer Bee or Iruka with breaks will add nice damage. If you fighting vs stronger enemies and want to live more Edo Itachi or Hokage Minato/Hiruzen are really good. I use Hokage Minato the most because on my server Kakuzu is most popular move 1 and he helps reduce damage a lot, but on newer servers i hear Edo minato is most popular ninja so might be different for you.