Nubbeh
I don’t think the bow will help him later on and since you said he didn’t feel anything soecial from the weapons he learned with kunai, shuriken, swords and bows are already out. You should also take note that he shouldn’t take a big weapon since a ninja needs mobility and not have too much extra weight this takes out spears, axes and hammers. But a weapon i’m interested in would be a blade with whip properties since most people just use a sword or spear in their stories it might be interesting to add a little twist, or maybe a tri bladed claw since i’ve never seen anyone use that
Because he have already practiced with shurikens, kunai, swords and bows and doesn't feel a connection with them they are out. As someone else said, as a ninja he needs mobility and shouldn't bring too much extra weight this takes out spears, axes and hammers etc. I myself recommend using senbon for long range/mid range attack, they are also useful for incapacitating people and medical ninjutsu, chakra enhanced strength like Tsunade for close combat and if he needs a main weapon I recommend chains, whips and tessen because it's cool and nobody ever use it.