ORIGINAL: mind_messing
Looking at the map, Wake and Marcus. He can advance in the center through the Marshalls, so I think you need to watch for the big right hook to Wake and Marcus that will expose the Marianas.
Okay: Wake and Marcus are both 6K Atolls very far from friendly air bases.
What are American worries:
Within Betty/Nell strikes but not much else. IJN KB is a worry.
Atoll: Limited to 6k troops defensively, Wake known to have the fearsome Wake CD unit (although they are elsewhere in this this game).
Solutions: Grab Ailinglaplap or elsewhere in the Marshalls and bomb Wake to negate the CD guns. Or, cushion your invasion force with lots of battleships and hit the defenses with carrier planes and other naval bombardments as you can. Provide air CAP over Wake.
To maximize offloading do you need to be there for two phases? Probably.
Divert the KB to the other side of the Empire. Or, depending on date, this would be a good place to fight the KB. Allies know the KB would come from the west most likely: Day 1 inv fleet spotted, day 2 invasion, day 3 move American carriers west of Wake looking for a carrier engagement as the KB is moved into position to strike at the landing? You could make this quite nasty by flooding the area with subs too.
Japanese Steps:
So, defenses: one AA unit. CD unit. Infantry to fill out the island. Mines. Mini subs: ideal placement for mini subs as they can't be scouted ahead of time (still they will all die like flies). Good search radius to maximize early warning. Glen equipped sub in likely gathering spot for invasion?
Prep a division to take the base back?
Standby IJN surface group to hit the base? Where could they be based at? Fast, with lots of torpedoes? Or heavy as in super heavies? How would they have air coverage on the way out.
Just let them take the islands and not commit any ships?
What am I missing?