Trying to replace the the current page structure with a tree definition is probably not going to end well. As things are now I guess the only option is to tweak the source code and make those commands require higher security privileges.
If you edit PageElementProvider.cs and change the below lines to use PermissionType.Administrate then only users with administrative permissions to a page will see these commands.
If you edit PageElementProvider.cs and change the below lines to use PermissionType.Administrate then only users with administrative permissions to a page will see these commands.
// (line 72-74 in PageElementProvider.cs)
private static readonly PermissionType[] AddAssociatedTypePermissionTypes = new PermissionType[] { PermissionType.Add };
private static readonly PermissionType[] RemoveAssociatedTypePermissionTypes = new PermissionType[] { PermissionType.Delete };
private static readonly PermissionType[] EditAssociatedTypePermissionTypes = new PermissionType[] { PermissionType.Edit };