The actual solution I'd go with that I've talked about before is just add an auto-combo option for anyone that wants training wheels.
In reality, I'd like for WHM to develop a new, more fresh take on its offensive gameplay. But let's say, for the sake of simplicity, that WHM changes to have a DPS library that is effectively a combination of the high points of its history.
Stone > Glare: Your filler single target. (Potency is 300)
Aero > Dia: Your 30 second single target DoT.
Holy: Your AoE filler. (Potency is 170) Gains a new effect where the potency doubles whenever a lily is added to your healing gauge, or something like that.
Aero III > Luminescence: AoE DoT that stacks with Dia. Lasts 15 seconds.
Water > Banish: GCD AoE attack with a 30 second cooldown (Potency is 400)
Afflatus Misery: DPS refund AoE for spending lilies.
Assize: OGCD heal/DPS action every 40 seconds.
Again, I'm not suggesting this as what we actually get, but I'll use this as a reference for the auto-combo example. You can either set these actions on your hotbar independently, or you can set the auto-combo action to your hotbar instead. How that works is that the button changes to a specific action based on a priority system that looks something like this:
Afflatus Misery > Luminescence > Dia > Banish > Holy > Glare. It starts at Misery. If you don't have a blood lily, it goes to your DoTs, if your current target has each DoT, it looks to spend your charges of Banish and your Holy conditional. If none of those apply, it defaults to Glare. There would also be an AoE auto combo that would go: Afflatus Misery > Luminescence > Banish > Holy. The only thing you otherwise use manually is Assize.
Every job would gain an auto-combo option for single target and AoE that would run through your GCD for you. Players have the choice to run with or without it. Done. Problem solved. Can we go home now?