Back in the day, everybody I knew writing post-"Chosen" separated Faith and Robin almost as quickly as they separated Willow and Kennedy.
This I get.
If part of the reason you're writing fic is because of the slash, you want to ship your characters the way you want, and there was (and still is) a lot of anti-Kennedy feelings out there. I mostly think it's from lack of imagination, because I find Kennedy an interesting character with a lot of potential. (Pun intended.)
Robin, however.
Let's start with Jonathan's murder. Jonathan is incorrect or insufficient to open the Hellmouth, so Andrew starts looking for options and gets caught. Fine. And then we see the principal of the rebuilt high school finding Jonathan's corpse and burying him in an unmarked grave. We've seen Flutie and Snyder deal with dead bodies on campus before, and they get police and ambulances and the whole nine yards. We don't know what's going on with him yet, and what we're shown doesn't look good for him. It looks like he's cleaning up the First's messes.
This is never explained.
When we find out about his real deal, we find he is the son of a Slayer, and seeking to kill Spike. Or, the triggered, out-of-control version of Spike.
He had to know Crazy Spike was in the basement. He could've gone for that much earlier than he did. But he did it late in the season because that's where there was a hole in the schedule.
Basically, I don't think any of us knew who he was and what his deal was, what his motivation post-"Lies" was, and if there was any reason besides matched pairs for that stupid "Empty Places" "everybody but Buffy & Spike fuck" for Robin and Faith to pair up, it is totally unknowable to anyone not in the writers' room.
I've seen "Robin's in Europe, hunting books", and I could definitely see Ninth Gate as a pseudo-Watcher story. Before "Damage", there was a lot fic about a "Slayer School", a sort of Dr Giles' School for Extraordinary Youngsters, and if there is a school, we have a built-in principal. But I almost never see him involved.
Is there fic out there where Robin is portrayed, where he isn't a punching bag, and where Faith/Robin is portrayed?