The FlexDeploy permission model offers great flexibility for managing security. However, you must understand that with fine-grained security comes the overhead of needing to configure and maintain it. You should avoid managing permissions at a level lower than you really need. For example, if you choose to manage all security at the individual project level, you will need to configure the security every time you create a new project. Instead, if you establish permissions near the top of the folder hierarchy, you will only need to configure security when you create new high-level folders or when your security requirements change.