I'm the CTO of a company, so I'll answer your original question.
One of the areas I'd love to see a SaaS product solution is reporting. Developers like myself often just focus on building the product and if they're smart, like yours truly, we add analytics.
But getting a clear picture of the business can still be difficult with different people on the team preferring different methods of communication. Some of our stats go out via email, and the people that like email only see part of the picture. All of our stats go over Slack, but not everyone likes Slack. I ended up building weekly email reports that totals everything up and gives the single, clear picture. Not every team has this capability though, and a single API to report significant events in the application with configurable communication methods for reporting and notifications would definitely be something worth paying for.
Along with other people in this thread, I'd definitely recommend talking to as many developers and companies as you can to identify real problems, rather than looking for one where it may not exist.