While we work on sub document permissions there are a few tips and tricks to help you prevent accidental user error as others work in your doc. Do share things what are working for you.
- Create a section where you explicitly ask users to stay away from.
- Hide your tables - ( using a filter and table option)
- Create views that show users only rows meant for them
- Create buttons to add rows to make it easy and scoped.
- Adding automation notification that get triggered if incorrect rows are edited.