There seems to be some confusion here. I'll try to unpack this.
Using Hand of Healing as an action.
Hand of Healing says:
As an action, you can spend 1 ki point to touch a creature and restore a number of hit points equal to a roll of your Martial Arts die + your Wisdom modifier.
If you use Hand of Healing as an action, you cannot use flurry of blows ...
The extra healing from Chalice is not from a spell
The effect doing the extra healing is from the class ability, so the total healing is "8 + 1d8 + double wisdom modifier" as you stated.
The cleric ability only affects spells, so it cannot maximise the healing from the druid ability.
Consider not having healing
D&D is a game of choices, you always have to carefully weigh up the cost of choices.
Spending a feat uses up a valuable ASI. Choosing a multiclass uses an entire level. Even spending 50 gold is 50 gold you can't spend on something else, plus it takes up room in your backpack and weight on your back.
We often feel that we ...
If you have time and money, you can make your own potions of healing.
Someone with a herbalism kit and the proficiency to use it can craft potions of antitoxin and healing.
PHB, Chapter 8, Between Adventures, Downtime:
For every day of downtime you spend crafting, you can craft one or more items with a total market value not exceeding 5 gp, and you ...
Greater restoration does not give special knowledge of the effect it cures.
Spells only do what they say they do.
The caster must choose which of the five effects of greater restoration to use (PHB, pg. 246):
You imbue a creature you touch with positive energy to undo a debilitating effect. You can reduce the target's exhaustion level by one, or end one of ...