I have doubts about the WCF at the time of its implementation that it would be appropriate to create WSDL for each entity that has the exampleServiceService a WSDL in which usually carries the CRUD methods or a single WSDL that is named for example ErpService and that contains all the Methods that interact with all the existing Entities of the system. Greetings
for me the WCF Services are they are a logical encapsulation of a business functionality. With respect to your two proposals, I would go a little further and make the implementation based on functional blocks and not entities. For example, an Inventory (InventoryServices), Validations (ValidationService), Sales (SalesService), Purchasing (PurchaseService) etc.
It all depends on how you designed the system.
In my case, I have the WCF layer that affects all the entities and it is the only one that has access to the logic of the business.
My WinForms application follows the following structure.
APP (Winforms Client) - > WCF - > BLL (Business) - > DAL (Data)
in this way all processes are executed on the server side through the WCF
Greetings,