Need to say that r/p AOE is not so strong anymore after upcoming patch like warriors AOE. r/p is nerfed to 6 targets.
But yes, S/M AOE is too strong in my opinion as it I already said.
You forgot to mention that Holy Surge gets capped at 6 targets, BUT gets buffed in terms of damage.
Moreover, R/P still has the same excellent burst damage. Out of all Warriors (if not all classes across the board) only /Ch can keep up with that. Moon Cleave in its current(290x3) state is too weak compared to most other AoEs. It's only worth using in burst and even then doesn't do much damage. R/P on the other hand has very good sustained AoE and especially excells at damaging smaller packs.
W/Wd has a weaker non gcd spammable, singletarget and AoE. Not to mention that they both don't do elemental damage like Kick & Holy Surge. R/P has a very strong, permanent patk buff. I'm absolutely positive that W/Wd can't keep up with that after the Moon Cleave change.
W/Ch has the same burst potential like R/P I'd say, but looses in terms of sustained damage. We'll have to see how this plays out.
And thats even without taking into account, that R/P is much, much more tanky than any of the two, thanks to Patience and Salvation, Holy Surge & Target Defense iss.