It's so annoying to see how even though engineer, revenant and necromancer all have viable healing builds, most groups will specify that they only want a firebrand or druid. Just really sucks that the support classes are so unbalanced so that firebrand and druid are pretty much the only meta. There's almost never any specifications for damage classes because for the most part every class has a decent damage build, but even though there are nine classes in the game only two are support meta. Yet as said; engineer, revenant and necromancer have healing builds while thief and mesmer have fragments of them.
Doesn't seem like much effort has been put into balancing the support meta so that each support class brings a unique benefit which makes them all similarly appealing in end game content.