Dynamic Web Application UI Creation Using Angular

We want to develop the following Angular modules: i ) User Admin ii) User Details User Admin module: 1) Responsible for CRUD operations on users. 2) Defines Roles and permissions for users. 3) Relies on REST Apis exposed by a server. 4) The user must be able to visually design the parameters for each entity, like users, roles etc. i.e, The user must have a "ToolBox" of controls from which he can "drag and drop" controls to define the parameters. The "ToolBox" should be extensible. i.e, We should be able to add user-defined controls to the "ToolBox". If this is not possible, please suggest the best approach available in the industry. 5) We should be able to switch to a different template easily. User Details Module 1) Displays the user details defined by the admin module for a particular user. 2) Should be able to load UI dynamically (using JSon/XSLT) for the entities defined at step (4) above. 3) Should use the same template as the Admin Module; but with different color. The application should use standard software engineering principles (like SOLID,Dependency Injection, Testability etc). I am expecting some one who has worked on enterprise level web applications to develop this feature.