Honor point gain is based upon the Fame of the creature honored. Fel has double Fame. You also gain +1,000 Luck bonus in Fel (which isn't displayed), which affects the loot Thrasher has (can sometimes get some good Jewelry from him), as well as the chance for ML drops (like Pads of the Cu Sidhe/Quiver of Elements, which are both still useful).
Honor gain is also affected by distance from the honored target, letting the honored target land the first blow (very minor Honor boost, i don't bother with it), and Honor gain is greatly reduced if you use Poison Damage (either from Element or spell), so Poison damage pets are awful for gaining Honor.
