This is a tough question.
Most customers use the SQL Server native client; however, they made this decision years ago. Considering Microsoft has discontinued the native client, its not clear that going with native client for a new project such as yours is prudent.
The issue with ADO.NET is the install/config for each desktop user is a hassle. Of course, if you have other .NET desktop that require this then there is no additional hassles.
Another thing to consider is what is your future plans for your app? Do you plan to use the .NET DataStore and/or convert existing business logic to REST APIs? The .NET DataStore uses ADO.NET to interface with SQL Server so you might simplify development by standardizing on ADO.NET for both your client and server-side code.
We are working on a "new" MSOLEDBSQL driver interface for SQL Server as migration path for existing users of the native client, but it won't be available until the next version. So given the timing of your project, this may not be an option. But anyway, wanted to throw this out there.