I remember back when I started in SB, even though my primary job was PLD, when I made my current character, I wanted her to be a healer, so I started her with CNJ and picked up ACN along the way for SCH. Even early on, I was expecting to have to be constantly healing because I "only had 3 or so attacks". I got proven wrong fairly quickly, but liked that I had that downtime to throw stones and suffocate the mobs with Aero in between topping up the tank. I remember a tank back in a lvl 50 dungeon being surprised that I was actually using Holy on large mobs, getting that long cast off in the middle of a large pack felt good. I had a decent enough time upkeeping Aero and Aero III between Stone casts, but it did feel a little lackluster once I got to higher levels.
SCH however was a different story, I had 2 extra DoTs to use, and I loved making the most out of my Aetherflow between Lustrate/Indom uses and Energy Drain or Bane. It was very fun to keep those DoTs rolling, and incredibly rewarding when I took that risk on Energy Drain usages, especially when I got unlocked Quickened Aetherflow. WHM felt anemic after that, WHM had to rely on basic heals that didn't feed back into its main gameplay loop, and only had 2 DoTs and a nuke, it was no wonder I thought that people complained about it back then, that it had no identity apart from "make green number bigger". How much cooler would it have been if it followed in BLM shoes and had a focus on long cast times, managing instant casts for that needed movement, and a healing loop that fed back into that damage loop? If SCH could do it with its oGCD heals, why not a healer that wants to use its GCD heals? ShB, for all its faults in healer design, at least did that right in my opinion.
WHM I think only needs like 2 more DPS spells before I'd say it's at a stage where I'd be happy with it. I memed a bit on the healer forums with a WHM rework that copied BLM's homework, turning Astral Fire and Umbral Ice into a healing stance and dps stance respectively, but I liked the idea that Banish gives 3 buff stacks that lets you use Glare and sometimes procs Banish III, so the base filler becomes Banish > Glare x 3 > Banish / III > Glare x 3, etc. I then had Dia change from a DoT to a cooldown with charges to make it a movement tool and I'd honestly be happy with that kind of rotation, simple, but still engaging.