|Maybe the problem isn't with who they cast as the Doctor maybe it's that they need to bring in an older companion. David Tennant and Bernard Cribbins (Wilfred Mott) made a great pair. Hell even Donna had her moments. So maybe they need bring in someone who is older to off set the Doctor.|
Then I had a conversation with a friend this weekend and I think we worked out part of the problem. It's not so much the age as it is the role. Comparatively, the companions from the classic series were sent off to do things and trusted to not get killed on their own, while the companions in this new series are constantly being told to stay put and not touch anything. We then realized that's partly why we both found ourselves enjoying Donna's season more than Martha or Rose's, and classic companions to new ones. They both got taken by the hand and lead around, helping out where the Doctor told them to, whereas Donna would actively offer up help (like using her awesome Temp skills ("Doctor's Daughter") or knowing realizing where the exit would be in The Library ("Silence in the Library")). When we looked back at the past, especially at Sarah Jane (because we're both big 4th Doctor fans), the companions used to take smart initiative or bring something especially useful to the table. They learn to work stuff out (even for technology they aren't familiar with) and learn to offer up good suggestions and plans. They don't do that quite as much anymore, save for Captain Jack and Donna.
Of course, taking that a little further, I was then comparing the relationship with the Doctor and his companions from classic versus new. It's almost that the Doctors in the new series don't need a physical companion so much as just a voice to tell him when to do certain things. In the classic series, the Doctors actually needed the physical assistance from the companions. At least for me, the more classic series I watch, the more I find myself preferring a Doctor who can't do it all (even if he can think it up) to one who can. A Doctor who can do it all and just wants the companion to sit around doing nothing doesn't really need a companion after all, does he?
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