If there's one thing the audience has learned about the Doctor, it's that he can take the lead and solve problems in any situation. Have the TARDIS crash on a spaceship run by special operatives within the Galactic Alliance (or whatever you want to call a local group of sentient races), and the Doctor has to travel with them for a few adventures this time, he's their companion, in an odd sort of way while he makes repairs. Alternately, have the TARDIS crash into a previously unmet species' passenger ship and damage it. In order to save the passenger, he takes it on board and does his best to look after the creature whose biology is completely unknown. It's now a race to find not only a way to get the creature safely home (or to its original destination) while keeping it alive. Instead of having a companion, he has a passenger, not necessarily able to fulfil the more usual role. Another possibility lies in the possibility of TARDISes lost in the Time War, abandoned by owners who failed to survive. Imagine what happens when the Doctor finds one during a story (perhaps we saw this in "The Lodger") and it decides that it wants a new pilot and takes off with him. Imagine Sexy (the Doctor's TARDIS) coming to his rescue, companions in tow. There are so many exciting opportunities for exploration, and the series needs to take some of them.
Michael Marcus is a game designer, author, and mad scientist living in Hamtramck, Michigan; his current project list include a series of comic short-stories collectively called "One-Punch," a book on hypnosis and language called "The Prometheus Codex," a collaborative game project called "Art War," and a fun spy story called "The Adventures of Jack Uzi" at http://tinyurl.com/JackUziChannel (for those interested).
