Myself, I think that Japan could have landed perhaps 4-500 marines somewhere in the islands and perhaps led a suicide raid to utterly destroy Pearl harbor, this would have been much more effective then a long land battle and im sure the convoy ships needed to support a garrison (If they won) could have been better used in the pacific.

If they succeeded in destroying most of pearl and the grisly ship hulls pockmarked the bottom of the port then it would have set back the USA at least 1 year in starting a pacific campaign.