Hmmm...this returns. Cool.
Okay, a few things to note.
In the first chapter, Kasumi asks the receptionist to find a "Dr. Hiyowai". Yet here you write that his name is Dr. Okamoto (specifically, Kanji Okamoto.) I suggest picking one name and sticking to it. And, I also suggest you change the first name because I doubt very many people in Japan are named after one of their alphabet systems. My suggestion is for it to be
Kanryu or
Kanryusai, as both of those start with Kan.
Kanryusai has the advantage of being the name of a real, historical figure -- Takeda Kanryusai (Kanryusai Takeda, to westerners) was one of the captains of the Shinsengumi.
On Dr. Tofu, I find it amusing that all of the adults are calling him that when it's extremely unlikely that any of them would. Tofu is his GIVEN name, *not* his family name. In fact, I think it would have been funny if he stopped allowing people (specifically, the Tendou family) to call him Dr. Tofu as a way of spiting Kasumi for not recognizing his bloody obvious affection for her. And then, once he'd gotten used to hearing it from them, he asked everyone to refer to him as Dr. Ono from that point out.
The name of Akane's husband (Shinki) is another one I find questionable. I suggest Shinji, Shinichi, or Shinsaku if you want it to start with Shin.
Next...hmmm...ah yes.
Ranma thought the most change thing about Nabiki were her eyes. Where once was a lively, mischievous, and greedy shine in Nabiki's eyes now was replaced by a cold, greedy, and hard look.
Ranma involuntarily shuddered internally as Nabiki sized him up like a shark would a choice tuna fish - or a buyer looking over a piece of property. Either way, Ranma felt like a nick-nack or a object under the gaze of the other woman.
"Amazing. You haven't aged a day," Nabiki commented as she continued to give Ranma the once over. "Still as pretty as I remember. Hmm..."
Ranma began to feel very, very uncomfortable at the look Nabiki was giving her.
Nabiki hasn't changed at all. Good.
I'm glad that there are people in the fandom who aren't willing to whitewash Nabiki's character as so many others do. Cheers.
***
On Gosunkugi: Was that the Heaven's Gate cult you were referring to? I find it hysterical in a dark fashion, which was probably your intent.
On Genma: I enjoyed the references to his own childhood, which is something I've rarely seen another fic touch upon.
On Genma and Soun: still the same stupid shenanigans. It's strangely comforting.
***
Well, I think that's all I have for the moment.