Executive Level Dashboard

Hi there, this is a pretty broad question - reports for your execs would be driven by what data you have in WF to report on (aside from native data), level of use by your users (to speak to data credibility) and what is important to your execs to see within the data you have. Custom forms are key to help you capture KPIs/data you want to track on a project, task, issue, etc. level. 
There is a blueprint that can give you some ideas (main menu > blueprints) here that can showcase essentially active vs. completed projects/tasks at various levels.

I've asked this question in the past too, as most of our leaders look to us(me) to provide what they think they should see, "don't know what they don't know", and tend to focus on the now instead of the past to help shape the future. 

As Madalyn suggests, there are a few dashboards in the blueprints area you can use as a starting place. Once you start giving leaders ideas you can build on it with their feedback.