There is no "best". It is entirely down to how you are playing, what you want/need the players to do, and what you have around them. Almost any combination of roles COULD work, depending on all those factors.
For my preferences, I would probably avoid RPM and BWM as they both roam from home and can leave you exposed in the middle. DLP & BWM is a bit better. Doesn't provide you a midfield runner, though. Again, depends on what you are needing from them.