- **Heuristics Externalization**: Theme classification rules moved to `config/themes/editorial_heuristics.yml` for maintainability
- **Enhanced Quality Scoring**: Four-tier system (Excellent/Good/Fair/Poor) with 0.0-1.0 numerical scores based on uniqueness, duplication, description quality, and metadata completeness
- **CLI Linter**: `validate_theme_catalog.py --lint` flag with configurable thresholds for duplication and quality warnings, provides actionable improvement suggestions
- **Editorial Documentation**: Comprehensive guide at `docs/theme_editorial_guide.md` covering quality scoring, best practices, linter usage, and workflow examples