Just back from Yokohama stay last week. We flew delta HND-LAX, spent the night at Westin LAX and flew to east coat next day. I’d do that again. Good break up of flight. It was 2 tickets, but less than HND-IAD on FF miles.
One suggestion, if you can swap hotels, I’d recommend Sheraton Yokohama vs. Westin. We swapped hotels after reading a review that Sheraton was in prime location. We passed the Westin on our can ride from port. I agree. Sheraton is next to train station, excellent shopping, and easy direct buses to both airports (and also Disney if yoi have time for a quick visit-tickets are $50-70 dollars). Nice executive/elite lounge serves decent breakfast/light dinner/open bar.