An intriguing archetype with a few implicit built-in world-building details: 

• In spite of the Blight, there must be enough soil and seeds available for the Herbalist to grow their component herbs.
• The references to alchemy suggest that Herbalism is a learned skill, not something that can be discovered innately. So that's already one possible story hook in itself; how did the Herbalist learn to concoct and use their oils? What the massage techniques?

By design, it already sets a more cheerful, upbeat, light-hearted option to the Bloodletter.

That said, it feels like a slight missed opportunity to introduce multi-type Archetypes. By explicitly drawing on both arbularyo and hilot traditions, it feels like an organic way to make a class that heals both Pestilence and one other secondary type:

• Flesh - The  massage heals physical symptoms of the disease (e.g. boils, lesions, rashes)
•  Soul - The whispered orasyon and hand movements drive out the spiritual corruption at the root of the disease

This has a direct effect on possible world-building, since the rules state:

Make sure your character’s healing ability is related to the problems faced by people in your world or caused by the Blight

An explicitly multi-type class potentially invites new ways to conceptualize the Blight, especially when combined with options from the Post-Fall Features prompt table.