Devotions for Aether AAR Spellbinder (Revenant vs Bysmiels vs Viper)

I noticed they all have resists reduce on last node but I can't see what the final amount will be for Revenant or Bysmiels because you have to level those final skills but Viper provides 20% and only uses 4 devotion points compared to 5 and 6 for the other 2. Also it looks like Bysmiels gives pretty decent generic stats like +30% all damage, 5% Casting Speed, Vitality resist, and a little OA. For an extra devotion point in Revenant I would get 60% Aether, 4% cast speed, more vitality resist, and a good chunk of health (6% plus 250), and a little energy absorb/leech.

After typing it out I think I've talked myself into Revenant. The other 2 looked appealing due to a combo of similar functions and less spent points. No reason I should get more than 1 of these 3 for my AAR Aether damage build right?

I was thinking about Behemoth after I fill out one of the others mentioned as it looks like it adds tons of health and regen. Is Behemoth as good as it looks or should I consider something else? I have 20 Primordial (blue), 8 Chaos (red), and 6 Eldritch (green) as of now. The only defensive focused ones I currently have are Eel, Sailors Guide, Lizard, and Vulture.