I've had the readings of Riley as threatened by Buffy's strength in an indefensible way pointed out to me, and I can't deny they're defensible. But I always thought that the Buffy/Riley relationship was meant to be a fairly feminist satire of the typical romantic relationship between action heroes and their wives/girlfriends, where the partner is typically expected to provide uncritical love and emotional support when needed, and to keep out of the way at other times. I think Buffy does act towards Riley that way at times, and that the relationship might have been intended as a role-reversal of that and a demonstration that feminist female heroes shouldn't just ape male action heroes to the point of taking on their dodgier aspects.