One thing Akane pursues throughout Ranma 1/2 is recognition as a martial artist. She never gains it, but she doesn't give up, either. Windstorm makes a point in that Ranma inadvertently aggravates her insecurities, and this doesn't change because she isn't engaged. However, Akane's relationship with him may be better than in canon, or it could very well be worse. On the "better" side is that nobody is trying to push them together, allowing any attraction that does appear to grow more naturally. Whether romance does grow between them relies directly on if Ranma or Akane have other viable romantic interests. In the original Ranma 1/2, Ranma ended up attracted to akane partly because she was the only girl (and only person period) who wasn't constantly trying to get something out of him. Likewise, outside of Dr. Tofu Ranma was the only guy in Akane's life that treated her like a person and displayed genuine concern for her. They got along horribly, but Ranma didn't have anyone else he could trust, and Akane didn't really have any other options, romantically speaking- she gave up on Dr. Tofu, and Ryoga isn't around enough. Without romance being rammed down their throats, a more healthy relationship could easily develop, especially if the have to work together to rescue the engaged sister.
On the other hand, if there is other romantic interests on either side, things could end up a lot worse. Akane spends a lot of the time on the wrong end of gender roles- it's one of the major reasons she can't get anybody to take her seriously. It's also the reason all the challenges for her hand and the Tendo Dojo go to Ranma. If they are not engaged, Akane isn't the target of random suitors. Being foced leave the defense of her sister up to "that boy" will grate on her, but she could accept it. Being forced to defer all challenges against the Tendo dojo to Ranma will quickly make her bitter. Without an engagement to Ranma to deter the hentai horde, they'll just keep coming throughout the entire series. Without the cover of the engagement and the balm of mutual attraction, what was "Ranma defending her" becomes dismissal, disregard, and a cruel deconstruction of feminine gender roles. Akane desires to be both a woman and a martial artist. Realizing that the people around her considers these mutually exclusive is going to hard for her, and will likely be make her very bitter indeed. Ranma will end up being a focus for that bitterness and anger, simply because the only other two people she could blame are Kuno and her father. She already hates Kuno, and it's going to take time and serious insensitivity on Soun's to overcome Akane's love for her father. She's quite likely to try and cosy up to Shampoo and the Amazons, simply to get training and sparring partners who won't hold back on her.
Another possibility is that she discards her femininity completely, instead aiming for an androgynous, asexual look. However, it would be more fun if She decided pull a Ukyo and pretend to be a guy. While this seems absurdly out of character for Akane, she might do it to spite Kuno, Ranma, and her father- especially if they make it clear there's a connection between her not being treated as a martial artist and her being a girl. She might very well decide that the only way to be taken seriously as a martial artist is to stop being a girl. More importantly, it allows her to one-up Ranma, Kuno/the Hentai horde, and Soun all in one go. Against Soun, it's a shocking, nasty act that shatters his peception of Akane as his little princess. In other words, classic teenage rebellion. Against Kuno and the hentai horde, if it doesn't get them to stop she might feel it's worth it merely for the looks on their faces. In addition, if she can excel as a guy it's the ultimate insult- "You boys are so pathetic, that I can be a better guy than you. Easily." Since Ranma's curse makes him insecure about his masculinity, he'll won't be able to ignore or dismiss that challenge- which works out very well for Akane, as she finds a way to get Ranma fight her and not hold back. If cross-dressing gets both the hentai horde to leave her alone and Ranma to take her seriously all in one go, she might very well decide to keep doing it. In addition, since Akane is a girl, it's more or less impossible for her to cross-dress as a guy and not look bishonen. Throw in the fact that Akane has a kinder and more pleasant personality than either Ranma, Kuno, or pretty much any other guy in Ranma 1/2, and you end up with the fact that a cross-dressing Akane will likely attract more girls than the rest of the cast combined. From a literary perspective, this is hilarious and full of potential. From Akane's persepctive, it's something she can lord over Ranma.