Your argument against it is that players who dont need to dual spec wont be able to get dual spec and instead should be handed a p2w visa card rune for doing nothing.
Its not that its “easy” or “hard” … its a QOL thing and something they could put in a rune which doesnt impact player power at all versus another ability / passive that will drastically shift player balance.
Not a very creative suggestion but maybe for warlocks a rune that makes rain of fire be like the NPC version of it where you target an area and it does the AoE without having to channel it, though it gives rain of fire a CD for the duration
Immolation aura-transforms hellfire into immolation aura, damage done to the warlock and mobs remains unchanged. (Lets be real, immo aura and hellfire would be busted).
Backlash-30% chance when hit to make your next incinerate, shadow bolt or immolate instant. (Covers numerous bases, gives meta lock a way to actually use these spells when tanking and a solid pvp tool)
Unstable affliction- cause why not, dispel protection and damage for aff locks.
Drain soul- when your drain soul deals damage, your current corruption and curse of agony flare up, dealing X% of their damage. Drain soul also gains the benefit of any talent affecting shadow bolt.(Gives aff locks a damage tool and something to click besides shadow bolt)
Soul flare- removes the soul shard cost from shadowburn, shadowburns damage is now shadowfire. (Gives destro locks a sustainable instant cast filler, also benefits from fire damage boosts.