You may want to ask a moderator to change the name of your thread to more reflect your question.

Whether JAL premium economy is worth extra dollars is an individualized question, but no one can answer it unless you say how many extra dollars it is costing for the flights you want, as compared to the other options.

As for the different airlines, Delta doesn't fly to Tokyo from Chicago, so you'd be connecting somewhere (presumably Minneapolis). Most people would prefer the nonstop on ANA or JAL.

ANA has both Haneda and Narita flights starting this fall. Which are you looking at?