Hawaii on round 1 is a pretty dicey proposition.
With no shore shot hits, the odds are about 20% of taking the Island.
If one shore shot hits, you are at 41%.
If two shore shots hit, you are at 76%.
Yes, you can get a third shot, but I would count on three hits.
This assumes that you attach the Islands with all three transports including 3 infantry, 1 artillery and 1 tank (max 5 units since you only have 1 at Caroline)
Bottom line is that you need to be fairly lucky to take Hawaii round 1.
I think the payoff is huge, but I can’t reccomend building your strategy around something that has such a high chance of failure.
If you fail badly (brick) then the counter attack could be pretty ugly. The US has 8 planes that can reach along with 5 ships. That is 13 total units. You have (If I recall correctly) 15 total units that can reach, including 6 carrier aircraft. You will likely win. However, since they will be getting a check for $62, they can afford the losses, but you probably cannot. You gained nothing on round 1 except a few territories in China.
Too much of a crap shoot for my tastes.