Templars are the only class with a healing skill tree.
The other option is a Restoration Staff.
So... If I want to play a dedicated healer, basically my only choice is a Templar with a Restoration Staff.
Every other class can turn into a DPS / Healing Hybrid by using a Restoration Staff, but I just doubt that one skill tree is going to make it incredibly viable for them to be a dedicated healer.
And, in the best case scenario, all you need to be a top notch dedicated healer is a Restoration Staff; that's still only two options.
I guess I'm just confused on why there's so few choices for a healer, and why they decided to remove the Warden.