3. Adventures Of Rose And The Meta-Crisis Tenth Doctor
When the real Doctor was dropping off Rose and the duplicate Doctor back in bloody Norway, he gave a chunk of the TARDIS crystal to the Meta-crisis Tenth Doctor so that he can have his own TARDIS in the parallel universe and go on his own adventures because sure enough, it needs saving too. The calculations then made it seem like it would take thousands of years for the TARDIS to grow, but in fact, its only 59 years until Rose and the Doctor take on the galaxies once again. This wasnt shown in the actual television series but was pretty existent as a deleted scene, which, if one recalls, gave some incentive to a possible spin-off. It wouldnt be the same at first, but its definitely something everyone would look forward to. Imagine all those places that Rose couldve gone with the Doctor but couldnt. They could go to Barcelona, where there are dogs with no noses, or go the planet of hats, or basically, theres not much that can stop them from following their destiny now. Rose will travel with him forever.