Thanks for the ideas @kkinderen! Do you mind sharing a couple of your Pivot Table topics? I use them so much for other Google Sheets, but have never thought to bring them into my Tiller sheet!
I am a big fan of the Category Rollup Report and Category Report, but they are static and have to be manually created each time you want to use them. I can see how a Pivot table could take over some of their use cases!