i have a lv270 shinobi at krToS. this is what i have to say.
2 strong attributes for PVP:
- stealth 8 seconds when using katon no jutsu (required 2 bombs)
- mokuton no jutsu’ attribute make the target stalled for 5 seconds but he can still attack from original position
speaking about bunshin no jutsu. i will say, it is pretty weak DEF once you summon clones. if you do not handle it well, your HP will drain fast and even to dead. for me, swordman c3 for bunshin is quite no meaning. i would prefer to get highlander c3 and max skyliner lv10 and doppel’s cyclone lv5.
kunai is the best attacking skills so far. bunshin no jutsu multiply the attacks with clones (5 for max). it works good too without bunshin no jutsu. generally, bunshin no jutsu is used when only good timing. cast it all time will endanger your life 
mijin no jutsu, i think there is a bug inside this skill now. it is slow and hit almost hit nothing. before the animation completed, you are already dead hitting by mobs or PVP players.
mokuton no jutsu is worth for 1/5. kunai is worth for 5/5, bunshin no jutsu 5/5, katon no jutsu is only using for hide so 1/5. the rest of the skill points, it is up to you.
if i were you, i will choose this way:
swordman => peltesta => highlander => highlander => highlander => doppel => shinobi
the best attack weapon is 2 hands sword. don’t choose corsair c2 for 2 type weapons because the attack output damage is very very bad.