I'll admit that reporting design is my weakest skillset (at least in the data realm) - so I had to evolve a framework that myself + the team could easily follow.
How we design report pages:
- Perspective: What changed, and is it good or bad? This is often delivered via scorecards or a simple table.
- Drilldown: What segments or cuts can we explore that drove that change? This is where pivot tables with expand-collapse + filter-on-click come into play.
- Action: Line-level details (usually in a table), that someone can take action on (ie this specific campaign needs adjusting, this specific landing page is performing well and should be boosted, etc)