hm, i dont know. he is smart enough and apart from tsunade he would be the best choice for konoha, but i think he would loose to any of the current other kage.
kamui's preparation-time is to long and it's to easy to evade or block. apart from kamui he just lacks the "bamm, you are dead" technique, that e.g. tsuchikage and raikage have, nor does he have the long-range-hard-to-evade-jutsus that e.g. deideira, sasuke, gaara and probably the mizukage have. That would be ok, if he had the endurance that naruto has, so that he can create a trap of multiple jutsus to hit with raikiri, but it's the other way round, 5 jutsus and it's over for him. and he has no defense apart from his speed, which is just slightly above average.
so all in all, his strength is just above anbu-level, not really kage-level.