I would have grouped Ra's al-Ghul under the B-Lister category, to be clear. Never heard of him before Batman Begins and it's really Liam Neeson that manages to make the villain work.
I'd say that, in terms of the comics, Ra's is borderline A-list, but in terms of cultural perception he's C-list, down there with Man-Bat and Scarface.
Ra's hasn't always
been A-list in the comics, though, which is why I call him borderline. He goes through periods where he's used a lot (like now, for instance), then he'll go years between appearances (like the 80s and 90s). He is definitely an important
Bat-villain (and, in terms of the current comics, Batman, Inc. could likely be Bruce's latest gambit against Ra's and the League of Shadows), but he's also a one-note villain. There's not a lot to his motives and goals beyond eliminating Batman because he spurned both his daughter's affection and Ra's offer of alliance and eliminating the world's population because the Earth is overcrowded. He's difficult to use well because he's such a global
threat; Batman stories that use Ra's usually turn into James Bond-type stories with globetrotting, impregnable fortresses, and the bad Bond girl.
On the subject of Talia and recent Batman
comics, Red Hood: The Lost Years
charts an unexpected development in her life. I closed the sixth issue and said, "Wait. Did that just happen? That didn't just happen." It wasn't a bad series, and the continuity backfill was handled well enough. But that thing with Talia...