I 100% get that! I guess I was just looking at it from the perspective of that both of her past relationships ended poorly (for different reasons, of course). So maybe it would be beneficial for her to reflect on who she is with and without magic, who she is individually, etc. However, I see what you're saying from a logistical standpoint. She and Tara were groundbreaking representation, and after they made the decision to kill off Tara they probably didn't want to cheapen the depth of their relationship by making it seem like experimentation. I do maintain what I said about Kennedy, though. If the writers wanted people to care about Willow's season 7 relationship, they should've 1. put her with a more likeable character and/or a previously existing character and 2. had them meet sooner; half a season isn't enough time to care about a relationship in a show's final season. I guess that relates to the topic of this thread; people disliked that relationship so much they started putting Willow with any other character they could haha. And I don't blame them!
Another thing to point out is that a lot of people seem less tolerant of bisexuals than you'd think. (Not saying you LOL, this is again a general rant.)
So what if Willow went out with a man after Tara? That would not mean it was a phase or that she didn't love Tara. It would mean she was bisexual, which would be a FAR better reading of her character by the way. How does she go from almost killing herself over a man cheating on her, being unable to physically keep her hands off Xander to the point where it ruins two relationships, be seduced regularly by male monsters like Thomas and Malcolm, all while never showing even the slightest bit of interest in any women, to now being unable to find a man attractive even when magic compels her LOL.
Latent bisexuality makes so much more sense. However people seem to think it just doesn't exist LOL, hence why if a woman is with dozens of men but then ends up with a woman again a lot of these lunatics go on about how she was comphet lesbian whatever that means, or if she was with a man, then a woman for years and years, and then ends up with a guy again that gets called a phase.
Of course this is not to say that you don't get lesbians in the closet and people dabbling. (I dabbled a tiny bit, though I'm definitely straight now.) Still in a lot of cases we have characters who have been involved in dozens of relationships with guys or women that were clearly at the time written to be genuine, not just repression or a phase etc.
Sadly so many bisexual people are often bullied into picking a side as it were.
Meanwhile as to why Kennedy bombed well I think it was a combo of reasons. As an idea for a character, she's not THAT bad. The actress is fine, she's gorgeous, she's a decent fighter who can actually hold her own with a Turok Han so she's not all talk and she is a nice contrast to Tara who as so soft. Also to be honest I have 0 problems with her when she calls out Buffy, which seems to be what most people hate her for.
She was right when Buffy was being a bitch about a girl who killed herself, and also I know this might cause a nuclear explosion, but I still have 0 issue with the potentials kicking Buffy out.
Thing is THEY DIDN'T. Buffy threw herself out. She said unless they followed her then she would leave. Her plan meanwhile was stupid. She wanted to drag a group of injured girls into a vineyard with Mcstabby the turbo charged woman hating serial killer, which had already got about 4 of them killed. The only reason her later plan worked was because she was on her own. Think she could have done that with 15 girls who couldn't defend themselves against Caleb? On top of that Buffy had also been violent to people who disagreed with her earlier, whilst Spike, her absolute simp was also violent to anyone who disagreed. Kennedy was right in that respect.
I also don't think it was because she simply replaced Tara as to why she was disliked. Tara replaced Oz who was beloved and Wesley replaced Doyle who was beloved and Spike replaced Cordelia on Angel who was the heart of the show and they all thrived.
I think it's more.
1/ As you say it happens too fast. Tara's not even cold yet, also within the first episode of them dating they practically have it that Kennedy saves Willow through loves true kiss LMAO.
2/ I think they sexualized it more than Willow and Tara. Other than Xanders creepy dream, Tara and Willow were treated normally, no fetishy "ooooooh girl on girl is hot." Whilst Willow and Kennedy? Nothing but that, with the worst bit being a "hahahaha look how gay Andrew is that he's not filming and perving over Willow and Kennedy shagging on the couch." Then there is that cringey montage of the Scoobies all shagging in the third last episode and The First being jealous of them. God I hate that bit. Definite director with hands down the pants moment. (Or writer.)
3/ They seemed to go out of their way to make Kennedy, well a bitch at times LOL. Again it wasn't even like they had her be rough and ruthless when it mattered or be a genuine foil to Buffy. All that stuff is fine. They deliberately did things like have her enjoy bullying other potentials for no reason, and only get to where she is at the top because she was shagging Willow, and other than her defending the girl to Buffy which was nice, there are no repercussions or moments where she grows or shows regret.
4/ She's part of the AWFUL potential slayer story that most people hate because it brought dozens of new characters to the already crowded cast and as she is the most iconic of them, well she becomes the face of that story (even if she wasn't even the worst part of it, IE they could have got away with maybe one or two potentials.)
5/ Also some people don't like the way she does pursue Willow a bit too aggressively. Again if that was a guy pursuing a woman like that then he'd probably be seen as entitled. (Then again people like Spike, but at least he has the decency to get his absolute arse kicked dozens of times and physically tortured for whole episodes LOL.)