I kinda assumed everyone knew that option and tried to cover it in saying "Lust at first blush"
Well, his version is more "oops at first contact"(ie accidental rather than "lust"), so it´s not quite the same even if it´s a bit too close.
So the stance your taking is that sex is inevitable if both genders are present and they are aroused?
No thought to even if they understand their new body enough yet to rationally understand the arousal?
Not understanding could be the very thing that makes things "hasty", if circumstances push. And it is the kind of thing that DO happen for real.
My teen years would have been allot less embarrassing if it had been that obvious to me
Well, the thing about "teen phases"/"feels" or whatever, despite all the shouting about how it happens same to everyone, no, it varies greatly from person to person, anywhere from chaotic disaster on legs to barely noticeable. My eldest brother was kinda average, my elder brother was a bit more towards the extreme, while i mostly got away easy.
In context it was being used more as a proof of heritage thing.
Ah, other way around... I´d say, if it fits perfectly, use it if you really want to, if there´s even a hint of having to make it contrived in any way, don´t even think of using it. Essentially, not worth the effort, there´s better ways for magically proving heritage.
While Genma might have seriously damaged Ranma's Romantic abilities are the Tendo sisters helping at all? Or any of the Nerima situations?
If you´re putting the story after he´s been at the Tendo´s for a long while, well then you have the issue that he definitely DO want Akane, even if he goes about it in possibly THE most awkward way ever seen. And Nabiki has made him paranoid and distrustful in general(helped a lot by "the fathers" and the bundle of crazies)...
Kasumi almost certainly has been a major plus, and Ukyo may have been a minor one... I would say Akane helps a bit as well, but it can easily be argued that she makes it worse as well(most likely both, even if i think the positive outweighs the negative simply because Ranma is forced to consider that he actually HAS feelings of any kind beyond that of a child).
But the issues caused by the male Kuno is potentially a MAJOR problem if you want Ranma as the mom. Ranma(chan) has been very negatively conditioned by him.
School and many other smaller events probably also adds quite a lot to the negative feel he has for girlside.
If you want it to go "easier" you probably need to catch him before getting to Tendo´s, or at the very least avoid Tatewaki´s insane stalking.
Don't forget the other side of the equation though. For this situation the girls have to end up in a situation to end up a Father.
Of course. I tried taking that into account when i considered them. Setsuna, she adapts, she doesn´t get disturbed easily even by the weirdest of stuff. Usagi, if she´s serious, different bodies would just be a minor obstacle to get past, and she´s VERY good at getting past obstacles.
Ami and Hotaru, there would probably be lots of blushing but that wouldn´t -stop- them. Ami is on track for medical studies and is more likely to be intrigued by weirdness than put off ( can´t turn of an analytical mind ), and Hotaru is simply too nice to let something weird get between her and a lover.
Rei and Ranma as a couple, unless they have a distinct reason to end up as such, i very much doubt they ever would, but IF they get over the unlikely coupling, their similarities might make them a very good couple. Rei´s more conservative and "proper" attitude would probably mess around with the genderswap, but if they´ve already gotten far enough to BE a couple, it will probably not be a major obstacle. Rei and Ranma would probably be the couple that would work out best if the cause was an arranged marriage(as opposed to such with the other girls i mean).
Minako and Makoto are a bit more wildcards, both could easily end up with Ranma, but both also have traits that might have him running away ASAP. And they probably would be more likely to have issues with being the male in the couple, but i don´t think that´s something that would be impossible to overcome, just might need a bit more effort.