They do look very good linking up with each other.
I'm not sure where this idea that that RVP will ruin everything comes from though. He could easily play in the role Hernandez did today. The problem is we have Rooney, RVP, Welbeck, Hernandez, Mata, Kagawa, Januzaj and Nani...and only 4 positions to play them in. Even with two games a week that's difficult when you also need to find a combination that works.
For me, Rooney, RVP, Welbeck, Mata, Kagawa and arguably Nani are all too good to be sitting on the bench every other week. Januzaj will be in the same category soon enough. I don't know what you do about that.
There's also the issue that at the moment, our fullbacks and midfield just aren't good enough for us to leave both our flanks light, which is why we keep playing Young or Valencia.
It's really not as easy as "do this" and it works. Though Mata and Kagawa are making a good case for needing to be in the team together...but then Welbeck is making a good case of needing to be in the team. So is Rooney. RVP even when he's playing badly scores nearly every time he plays. Januzaj is too good to neglect...