Nicely done. However, there is one thing that sticks out as a sore thumb. Complexity. You healers complain that you want healing to be "Complex" but everything that you listed is mainly not complex, at all. It's mainly buff this or bring back this. Also these changes you listed, there will still be downtime.
I don't know what you want in "Complexity" but in terms of healers, there's not much to be complex about. You're healers, you're job is to heal with minimal damage output. You're not a DPS/Tank. Should they make it more fun to play as a healer? They should try. How should they? I don't know but the things you listed certainly don't contribute much to the "Make it fun and complex" that you're wanting. As i said it's mainly "Buff this and bring this back". I feel like this list just scratches the surface. There's not much "in-depth" in terms of complexity and "Fun" of what you want. What is it that you want to change to actually make them more complex and fun? Just stating "Make it more complex" is very vague. And no, buffing skills and bringing back certain skills doesn't make a job complex and fun. The only thing that was "Complex" was Astro's original cards which you have listed. Everything else is just QoL basically with certain lines like "Change the healing style so it's not WHM-lite" - How? How do you want it changed? If you're adamant on changing healers don't list vague things and expect SE to read your mind.
Lastly, i'll revisit this thread next week and give some ideas of my own. It's been a while since i last touched my 80 WHM and in the midst of leveling my AST. I do need to touch up on my SCH as well.
Also on a side note, if i'm not mistaken - in the past live letters Yoshi stated they wanted to make things more simple so it's easier to play all around for everybody. This was for all jobs. Hence why some skills were taken away completely, etc. So asking for something to be more complex probably won't fly given the fact on how the Dev team wants to do things.