Thanks I don't believe the bow healer will be an effective trial healer, but definitely viable as a backup healer. The build is meant to be a DPS & healer hybrid, not a pure healer, so I wouldn't try anything too crazy! You may also have an issue with vet DLC dungeons, unless you have a really good party, but anything else should be fine. Also when line of sight is an issue (i.e. Darkshade II) I'd switch out Soothing Spores with Echoing Vigor instead.
As for Hircine set I think it's important to have as a healer, especially if you want to be part of a trial. Having that extra stamina recovery boost for 12 people is very attractive. As a healer you also want high regen anyway. But let's say you're in a 4 man setting, depending on the difficulty, you might be better off with a DPS set of choice.