Healing per se is not engaging in this game because of how encounters are designed.

in most of the content, in the scenario of your group managing to avoid all the applicable telegraphs, you can cover most of the healing with just free OGCDs, so that leaves healers without a lot to do. I think that to make the healer role interesting, they need at least one of these:

a) Revert back them having more dps tools;

b) Add a 'side-game' to every healer, just like AST has with the cards;

c) Change encounter design with a bit less telegraphed choreography and a little more random damage;