#1, where we have seen it the highest ranking/prestige bloodname holder is the House Leader . . . the only exception I can think of is whatisis Pryde that was CO of the Falcon Guard while Marthe Pryde was Khan- BUT he had the Aiden Bloodheritage which the Falcons were still swooning over. FREX, after former Khan Cyrilla died it was Conal Ward IIRC until Phelan became Khan and Conal was ousted the same day.
In Clan Blood Spirit, Sariah Church was the House Leader of the Church Bloodhouse, and she didn't appear to hold any particularly high rank (not a Galaxy Commander or Star Colonel on the rolls). The method of becoming a House Leader differs from Clan to Clan: the Coyotes elect theirs by vote, the Vipers have candidates duke it out in Trials, etc. So it's not set in stone by any means that the highest-ranking/prestigious Bloodname holder is the House Leader.
That said, I happen to agree with you that there's at least a decent chance that Anastasia
could be the House Leader for the Exiles' Kerensky Bloodhouse. Yeah, she wasn't popular in the Exiles... two decades and change ago. A
lot has happened since then; not only did Anastasia spearhead the reunion of the two halves of the Wolf Clan (albeit at Alaric's behest), but she's the one that took down Malvina Hazen in single, straight-up Clan-style combat, something that only Aleksandr Hazen was able to do. But there's also the fact that she doesn't appear to enjoy politics, so it's a 50/50 at best, I'd think.