I really wouldn't worry about the seats - that money is much better spent in Tokyo and as it is your first J flight with BA and you are in Club Suite you will enjoy it regardless.
Same goes for the food - it's impossible to predict what will be available for you on the day so my advice would be to go in preparing to enjoy all of it. A few glasses of champagne will get you into the right mindset too!
Savour your flatbed seat to Japan and let the rest float on by.