Happosai's has the same sound as a popular Chinese seafood dish in Japan also known as "eight treasures dish".
In the Japanese version, Principal Kuno's speech is littered with Hawaian pidgin to try and convey his otaku-like fixation on Hawaii. In the English dub, this is replaced with gratuitous Hawaiian, to convey the exact same point.
It was never revealed why Ukyo never told Ranma she was a female in the first place despite dressing up as a male and having a male name as a kid.
Ling-Ling & Lung-Lung may of been an inspiration for the manga only characters Pink & Link a pair of amazon warriors from China who made their debut in the manga sometime after Ling-Ling & Lung-Lung's debut.