Let's make a list of any house rules to consider here. No judgement, just a list for the time being.

• The Core Mechanic is very similar to 5e
• A simplified action economy
• Unique character generation rules specific to the Eldritch Earth setting
• Combat related rules and clarification
• Healing and Damage information collected in one place.
• A corruption system to track demonic possession
• A very simple but effective sanity system
• Custom rules with regard to recruiting and retaining NPCs and Retainers
• An innovative but OSR-flavored rewards system
• A new spellcasting library that captures the flavors of Eldritch Earth
• A spell Concentration rule that is similar to that introduced by 5e
• A master list of potential Conditions a creature might suffer

• A simple description of regular expenses and maintenance
• Directives for how to buy and maintain property and strongholds
• Rules for downtime crafting of mundane and magic items
• Information on how to request and carry out downtime side quests
• Details on how to use the “Western Marches” style campaign