Backstory: When starting a new business, tracking metrics is a pain. I've seen dozen of startups tracking KPI's in google sheets. The problem comes when you have to pull up these sheets, scroll and find the pertinent data... one central place would be great.
The Idea: A KPI dashboard that links to google sheets.
Deep Dive: You would build a platform where users can connect multiple google sheets and configure a set of graphs and tables from the sheet data.
Validation: There are a few products that can do something similar but keeping a low price point and targeting startups, you can find a small, profitable niche.
Monetization: Keeping the feature set small, you would charge a small monthly fee.