That’s a really good question @MisterFine!
Typically, when we start a project, we put everything in one schema (in prod, we name the schema analytics, and in dev we name it dbt_claire or dbt_drew).
As the project grows, we start to leverage custom schemas to logically group our models. We tend to use schemas that match our folder hierarchy, with schemas like core, marketing, finance. Our staging models often end up in a single schema, staging.
I’d love to hear what works for you!