The "modules" structure is also quite arbitrary, it is organized based on how the code is organized. Mostly this is a good thing, but since ERPNext is such a complex product with so many features, it is easy to get lost. Everyone has their own starting and ending point and the modules does not really make sense.
Add to Destkop
In an upcoming release, we are fixing this. You will now be able to add anything to the desktop.New Grouping in Modules
Along with this, we have also cleaned up the modulesNow you can see all modules together on the left sidebar and all the items of any module all together. We also re-grouped items within a module, for example instead of "Documents", "Setup". They are now grouped into more meaningful categories like Billing, Accounting Statements, Banking and Payments etc.