@NotASlayer It's certainly possible that the scar was pretty new- it would've happened during S1-2 of
Buffy & The Cleveland Hellmouth or something. But as I remember it was nasty enough to be permanent.
I'm not opposed to '
all wounds fade leaving no scars' being part of the slayer package but I also figure that slayer is human+ in all things, human to the max in terms of strength, agility, endurance, toughness etc but we know there's an upper limit on what they can do in all those categories.
I think that should apply to regeneration as well, probably because it makes the most sense, consistency-wise. And yes I know the show wasn't known for its high levels of consistency but whatever.
Hope that makes sense.
As for Parker and his appeal for Buffy; he was humorous, unassuming, faux-deep and non-threatening (
'vulnerability' for the term Spike used, deliberately); he also looked like Xander's cousin in terms of looks/behaviour. Basically he was a million miles away from Angel or anything like Angel and that was his subconscious appeal.
In 21st century parlance Parker radiated beta-male male feminist energy along with the accompanying sleazy/douche-y dark side. He was obviously douche-y, after the fact, and yet Buffy's tendency to focus on
her faults/flaws in a relationship is part of her character throughout the show.
I didn't think any of the Buffy/Parker stuff was out-of-character, I think it highlighted a flaw of Buffy's she conquers by the end of S7.