My wish list would be:
Freshly squeezed juices, especially for breakfast service
Beer - I actually quite like the selection they have already
Whisky - Aberlour A'Bunadh
Gin - Crown Jewel
(I suspect that neither of those would be allowed near an aircraft though, due to the high strength, A'Bunadh for sure is bottled at or just above flash point, and it wouldn't take too many Crown Jewel and tonics to give passengers their own set of wings, although it's not quite as strong as it once was)
Bubbles - LPGS