Your wish is present in the marketplace. Go to https://baseapplication-sandbox.mxapps.io to see how it works, log in via the top-right button, userid visitor, pwd Welcome12345!'
To get it into your application, download ‘System Management’.
To also have the user-information and personal image: also download module ‘Person’.
You can create a duplicate of the default layout, customize and use it.
In this custom layout, you can include a snippet and add css (maybe pull-right class) to move it to the right side of the top bar.
This snippet needs to have a dataview with source as microflow which returns the user account. You can use the pop-up menu widget from the market place inside this data view to customize your menu. You can customize the menu and it's visual based on your use-case from there.