The immidiate problem with dealing extra damage with a kama is that you would get a double damage bonus; one from the monk unarmed damage, one from magic. At level 16, you would probably deal something like 1d20+Str+5, to be compared with a Fighter that would deal 1d8+Str+7 damage.
Considering that the monk can do other things then fighting while the Fighter cant, it would be really bad if the monk had higher damage dealing potential.
Considering that the monk can do other things then fighting while the Fighter cant, it would be really bad if the monk had higher damage dealing potential.