Historical Data Modeling Catalogue / Workbench for SCD2, snapshots and temporal joins

What are the hardest historical modeling problems you’ve encountered in lately?

In our lakehouse environment the difficult parts are usually not Spark performance or ETL orchestration.

It’s things like:
• SCD2 dimension alignment
• Snapshot reproducibility
• Late arriving corrections
• Event-to-state alignment
• Historical relationship changes
• Dimension completion

I’ve been collecting these patterns and built a small workbench to reason about them.

Curious what other teams struggle with.