It depends on the rest of the team. If you were using a team based on only those Pokés, I would forgo Braviary/Togekiss and Milotic/Gastrodon to keep up the variety
The other four can be any non-uber pokemon... I just want a good starting core of two or three of those pokemon. I suppose Lucario and Gastrodon or Milotic and Roserade are the best ones, right?