Great breakdown. In my experience, many organizations are currently somewhere between Level 1 and Level 2.

One possible next step could be:

Level 4 – AI-Assisted Metadata Engineering

Business Requirements
↓
STTM
↓
Canonical Metadata Model
↓
AI Validation
↓
SQL
PySpark
DQ Rules
Documentation
Lineage
Knowledge Discovery

The interesting shift is that metadata becomes the primary development artifact. Instead of engineers manually translating specifications into code, AI helps validate, enrich, and generate engineering artifacts from a governed metadata model, while humans remain responsible for final outcomes and deployment decisions