The healer’s job sounds very easy: keep everyone alive as much as possible. Keep an eye on the HP of other players and heal accordingly. Of course you should still do some damage to Gorseval if possible, but it’s not your main priority.
The healer can use both Zealot’s gear or Berserker’s gear, or a mix. It depends if you’re willing to spend the gold and time required for Zealot’s gear or not, but Berserker’s should suffice. If you feel that the healing is lacking a bit, you can try to mix in some Healing Power from other stat types. Just make sure to not go above the toughness level of the tank. Your pets are the Tiger and the Bristleback.
Ideally all the armor pieces have Superior Runes of the Scholar or Superior Runes of the Druid.
Ideally these weapons have Sigils of Force and Sigils of Water.
The stats that should be included in your food and utilities are: