I’m in agreement on the main point here. I do understand why the healing arrows were nerfed - previously it was really easy to just sit back and watch a thrall do everything (see Firespark ), so I get the idea of a reduction to in-combat-healing, but we definitely need some kind of decent follower healing option for between combats. It is simply a matter of wasted time.
Giving thralls stacks of top-tier food (exotic feasts) does accelerate the process a bit, but after a heavy fight (such as the Arena Champion) it still takes a long time. And because there’s generally nothing to do but wait, it feels longer (if I can I try to find somewhere safe to ‘park’ and leave the room, but that’s often not going to be an option).
Whatever it is would need to be something that can’t be done too quickly, or it goes back to being used as OP in-combat-healing - which among other things is particularly likely to be damaging to PVP as it could potentially make enemy thralls ‘unkillable’. My suggestion would be to have bandages work on thralls, with the same time lock effect, but with the benefit scaled up to fit with follower HP levels (which have to be much higher because they can’t fight tactically the way a player can). That would allow a reasonable speed of between-combat-healing, without overpowering in-combat-healing.