There is one long standing character with natural ties to the book: Namor.
Part of the reason a heberal Alpha Flight title may be hard for new readers is that it already has so many characyers associated with the book. I don't think anyone should be added, but reader interest could be provoked if the team fights popular villains: Magneto, Skrulls, Doom, other X-foes.
As a f'instance, a battle with the Juggernaut in an AF style could be at least two unpadded issues of sheer actionL Sasquatch vs Jugs in the first, the entire team in the second.