In light of your recent interview, I'd like to provide feedback on what regarding healer design is too "stress-free" based on the many healer-related conversations that have appeared since most prominently Shadowbringers.
Healing
In order to heal, the party must first sustain damage. The balance between the healing resources we have and the damage we take is a delicate balance, one that has felt lopsided for a long time. We have too many free, accessible ways to heal in an environment that does not deal damage enough to warrant those resources. Every expansion has given us more and more ways to heal and DPS rather than heal instead of DPS. Additionally, many fights sometimes go an entire minute or longer without dealing any unavoidable damage to the party. Try introducing more frequent examples of manageable damage, more spontaneous aspects that can result in damage, and curate a selection of healing resources for each healer that don't feel like too much or too little for those environments.
DPS
Healers have far too few DPS abilities for how much time we spend DPSing in FFXIV. Healers do not need to have as many ways to attack as DPS jobs like Black Mage or Red Mage, but they should have a few more options that are unique to each healer. Look at the tanks for example; tanks are not DPS, yet they each have a larger variety of attacks that help make their offensive gameplay feel dynamic. Additionally, different tanks approach DPS with different levels of complexity, and the same can be done with healers. Much like how Warrior is a more simple tank, you can also have a more simple healer, but on the flip side, we should also have something like Gunbreaker, a more aggressive and fast-paced offensive healer. Before the release of Endwalker, you mentioned how during Sage's development, your team had looked at feedback of healers wanting more attack options and tried to explore those options with Sage, but the end result was far too timid of an approach. Why not be bold with Sage? Take a risk with a more aggressive healer design while approaching the other healers with more caution and see how it's received.
MP Management
MP is supposed to be a resource that presents the player with a choice on what tools they want to use to address different challenges, but MP management has become so automated that it may as well not exist, not unlike TP form pre-Shadowbringers. We need more options that allow us to spend larger amounts of MP for greater value. At the same time, we should also make MP regeneration something that the player has control over--not something restricted by cooldowns. If I overspend on MP, I should have a way to get it back, such as spending certain resources. Additionally, if we still want there to be a base level of safety when playing as healer, we can make very basic core abilities, like Glare, Cure/Cure II, and Medica, have no MP cost. This ensures the player can never lock themselves out of healing or basic attacking, but allows you to be more ambitious when designing new ways for healers to spend their MP.
More Utility
While Endwalker healer design has been under scrutiny, Scholar's expedient was a genuinely great idea and addition to Scholar's action list, and honestly is one of the best new abilities added to any healer in a very long time. Having a way to influence fights other than healing or doing damage is something a lot of people look for in support and healer roles. It could be really exciting to see each healer offer their own unique approaches to utility that allows them to approach fights in different ways.So how can we explore that idea more thoroughly? I know it can be a challenging task to come up with new ideas like this, but I think it's well worth the effort to do so.
Overall, there's been a lot of tension in regards to healer design, and DT is going to be a pivotal moment for a lot of people. Of the players who have not been satisfied with healer design since Stormblood, many of us aren't going to stick around for a third expansion of the same approach. Something needs to change, and I sincerely hope the coming benchmark trailer, job actions trailer, and media tour reveal a lot more than a new basic attack animation with 10 more potency and another heal that we really don't need.