Well, not DB design really, you can achieve the same thing by defining your POCOs well. I switched entirely to code-first design years ago. If you haven't worked with a good ORM, you're really missing out, though I admit there was quite a bit of friction at first.

No, I really am talking about how the database is organised. Tables representing objects, normalisation, etc. Whether or not it is accessed through the application with an ORM.