Again, it is shockingly unlikely that there will be any substantive change in the ETO. Germany First was the policy and nothing in this scenario changes that.
Midway was a great opportunity for the U.S. to bushwhack the Kido Butai (which, of course, makes the scenario under discussion here extremely unlikely, keep in mind that the Japanese never did locate TF 16 IOTL, so there is little chance of a complete elimination of the U.S. carriers) which, in turn allowed the U.S. (technically the WAllies since Watchtower had to be approved by the Combined Chiefs-of-Staff) to mount a shoestring, one division operation at Guadalcanal. Prior to Midway the WAllied strategy in the Pacific was to simply hold what was left (Fiji, New Caledonia, etc.) and conduct enough offensive hit and run operations to bleed the Japanese and keep them off balance. The WAllies will still be reading Tokyo's mail, something that provides then with an enormous advantage.
It is also extremely unlikely that the Kido Butai will be in any shape to conduct serious offensive operations, even if they suffer no ship losses (again vanishingly unlikely). The Japanese lost 13% of their total aircraft in the single strike on Midway and the two attacks against TF 17 resulted in the loss of 2/3 of the D3A on just one of the strikes. American AAA was, even that early in the war, quite robust, and the F4F was a much better fighter when properly handled than is usually credited (a look at the Japanese losses reveals a large number of losses to U.S. fighters). It is probable that overall IJN airwing losses, simply from air-to-air and AAA shoot-downs and "damaged beyond practical repair" would exceed 50%, especially if a couple strikes are needed against TF 16. It also needs to be remembered that the American carriers were close enough to Midway that many of their aircraft aloft (which would be most, since the U.S. had not yet abandoned the flawed "SBD is a a decent heavy fighter against torpedo bombers/recon flights" concept (which was true, provided the torpedo plane/snooper didn't have fighter escort, but not at all true if escort was present) at the time the last carrier was lost (or even before, as happened a couple times at Guadalcanal) could fly to Midway to augment the air wing there. That means the Japanese will need to have at least one, probably two more goes at Midway before landing the relatively undermanned landing force. So the U.S. carrier force is now two decks, pending the early 1943 arrival of Essex, but the Japanese are also effectively down to two decks until they manage to rebuild their air wings thanks to the IJN practice of considering the air wing and carrier to be a single operating unit.
The Japanese are NOT going to be able to successfully raid Hawaii again. That barn door was well and truly barred. The AAF had well over 200 fighters on Oahu at the time of Midway, headed toward 300+ by late summer IOTL. Throw in the on-going output from Douglas, Grumman and Vought that IOTL wound up on carriers that, in this scenario have no deck to land on, and there are better than 400 fighters, about 100 Navy/Marine dive bombers, mostly SBD, and well over 100 TBF now waiting for new construction sitting on Oahu and Maui. All of this is operating under strong radar (with the operators actually being listened to now) and a robust AAA, largely radar directed, heavy AAA and numerous medium AAA umbrella. To quote Sherman "If they will come this far, I'll send them rations".
In all there is little to no need to divert a single K-Ration from the ETO from what happened IOTL.
