If you mean any characters in the manga:
1: Itachi
2: Neji
3: Nagato
Leader: Shikamaru
All 3 eye techniques, plus the strategic prowess of Shikamaru= unbeatable.
If just current characters from the konoha village (Aren't dead, and haven't abandoned the village):
1: Neji
2: Shikamaru
3: Yamato
Leader: Kakashi (given he isn't dead)
Neji for scouting/strong tai jutsu, Shikamaru for strategy, yamato for his Mokuton jutsu just being plain useful, and kakashi for his battle prowess/added strategic intelligence.