What would an ideal API look like for storing FE settings in the database?

I'm thinking we want to achieve the following:

• PATCH for partial updates. New FE settings would be lost when using older FE if every save replaced all data
• JSON, keyed on software name so various FEs can utilize it and obtain consistency
• subkeyed for profiles? This would allow the power users to create named profiles so they could keep their desired settings. Also allows you to easily switch to maybe a "public" mode where you add more keyword filters, enable NSFW cover, etc.

Would love to hear your thoughts @hj @shpuld