Raven is extremely eligible. I know it's been in before and received fic. Time wouldn't make any difference to the eligibility; only the number of stories and whatever current rules are governing spin-offs.

At one point Amanda would've been ineligible because of her presence in the Series and the number of stories that fandom has. Last I checked, that rule was dropped. Even so, if I did nominate Raven, I'd be looking for fic focused on some of the minor characters, so whether or not Amanda was eligible would be moot.

I have seriously debated nominating Highlander: the Watcher, but I'm starting to suspect I may be the only one who liked it.