As taken from the wiki, these are the main tasks in the minigame;
Killing players - the amount of Zeal given is dependent on how strong the opponent is, and killing the same player multiple times will have lower Zeal returns over time.
Script does this, but given that your account is mid level, this is not viable
Healing teammates - players can use bandages on their teammates to heal them
Script does this, but gives you very little zeal from my testing, and like the above, you will die a lot
Burying bones - players can bury bones until their Avatar has 100% damage reduction.
The avatar can be at 100% for a good potion of the game, not allowing you to bury bones. Also, most bones would appear in areas with a lot of enemy players, causing you to also die a lot. But even so, I plan to implement this
Sacrificing soul fragments - players can sacrifice soul fragments until the opposing team's Avatar has 0% damage reduction.
Script does this
Dealing damage to the opposing team's Avatar
Script does this, but like that above, you will die a lot. Even maxed accounts may have trouble with this if the other team is defending
Capturing graveyards or the Soul Obelisk
Something I plan to implement, but like the above, you will die a lot
Killing NPCs (does not reward Zeal)
Script does this
Destroying barricades (does not reward Zeal)
Something I plan to implement, but in my option, is counter productive as you will receive less zeal overall
Given the above, collecting fragments is really the only option to gain the highest amount of zeal for a mid-level account. Because you have a mid-level account, you are going to die a lot, possibly not allowing you to offer any zeal, thus the lower zeal/hour.
No eta at this time