- the executives access this app how? (is Teams an option? What is the best practices here) / on the sidebar?
You can add the App into Teams or share the App URL with them and they bookmark it. Best Practice is depending on if your end-users are actively using teams.
- did I forget something?
Are using Dataverse as your Data source?
- should it be a security group? an office group?
Security Group is the best practice specially if your app will be integrated with other collaboration tools. - do I need to consider something with the environment, does this security group need to have access to this environment?