‘The Robot of Sherwood’ gives another hint at why the Doctor first fled from Gallifrey. This comes from Robin Hood, phrased in such a way that it would at first see to be part of his own legend. It is then revealed that this is the tale that Clara told Robin.
It could be that Clara changed some details so that Robin would bond with the Doctor over a similar cause. Yet the Doctor doesn’t dispute the interpretation and Clara, having lived through his time stream, might be in a privileged position to know the truth about what happened.
We have few televised details about the Doctor’s family and his station on Gallifrey. The title of Time Lord does suggest privilege but there have been few indications of wealth. This might indicate how the Doctor seems to have money to begin with and have difficulty with the concept of working.
The Doctor Who novel ‘Lungbarrow’ indicates that the Doctor does come from an important Prydonian House but the impression given is that they don’t live in luxury. The period covered in the book might be after they’ve fallen on hard times.
Robin Hood suggests that the Doctor was aware of how the rest of the universe lived and couldn’t stand it. That he stole the TARDIS to fight the good fight. This does seem to differ greatly to how we first meet the Doctor and his own account.
The impression given in ‘An Unearthly Child’ and other early stories is that the Doctor and Susan were wanderers. There were certain time periods that they found interesting but until Barbara and Ian joined them they weren’t interested in helping others.
‘Into The Dalek’ has the Doctor revealing that he didn’t even know what type of person he would be until he met the Daleks. This suggests that it is this encounter that made him first want to become a heroic figure.
We do know that the Doctor looked up to the heroic figure of the Corsair. There have also been several mentions of myths and legends that the Doctor knows well. It isn’t too much of a stretch of the imagination that there was always a romantic side to the Doctor, who aspired to one day be a hero himself.
If we keep with the parallel of Robin Hood we could question who was doing the oppression? It could be that it was the way the Time Lords themselves were treating the rest of the universe that compelled the Doctor to leave the comfort of being a Time Lord and fight for the ‘common’ people.
Certainly there have been incidents in which the Time Lords have treated the rest of the universe poorly. The greatest example of this is ‘The Trail Of A Time Lord’ where it is revealed they moved Earth, causing much destruction, to hide their secrets.
In ‘Remembrance of the Daleks’ it is revealed that the Doctor hid the Hand of Omega when he visited London in 1963. Rather than being a trap for the Daleks (who he hadn’t yet met) he could have taken it to prevent the Time Lords from using it. It could be that there was a plot to use it against innocent people and this was what convinced the Doctor to start his crusade.
This is the reason that he determines that he and Susan are exiles. If he was capable of getting them home they’d be arrested immediately, explaining why he believes they can never return.
Having hidden the Hand of Omega away he keeps a low profile, concerned about Susan. The encounter with the Daleks and other hostile races convinces him that there are other threats that need to be fought but he daren’t while Susan is still in danger.
Once he has made sure she is safe on Earth the Doctor becomes bolder. By his 2nd incarnation he has embraced his role as professional resistance fighter. Yet he is still afraid of his people, making it a huge sacrifice to contact them in ‘The War Games.’
The Doctor had his memories suppressed or removed prior to his 3rd Incarnation. It could be that they took this opportunity to remove the incriminating evidence that turned the Doctor against them.
This could explain why he is willing to work for them in his 3rd incarnation and doesn’t protest at the presence of Romana in his 4th incarnation. By his 6th incarnation he is reminded again how corrupt they are.
Using this interpretation, that the Doctor objected to the oppression of the Time Lords, there are opportunities for 1st and 2nd Doctor adventures where he does take a stand against his own people.
It could be that the Doctor knew about other ways in which they were controlling and oppressing the rest of the galaxy. When the TARDIS lands in the vicinity of where these plans are in progress he could try to stop them.
The Doctor would probably not reveal the true identity of the enemy they face to his companions. He’d also take extra care to prevent the Time Lords from identifying him or capturing the TARDIS.
This allows you to continue the Robin Hood parallels where the Doctor is a true outlaw, opposing the Time Lords. There could be a reoccurring villain, assigned to restore order and bring the Doctor to justice.
There could be later adventures in which the Doctor discovers that he was once opposed to his own people. This might begin as a mystery, with the Doctor initially believing he has been framed for crimes against his own people (possibly by the Master) only to discover he had a very good reason to do the crimes he is accused of.
This could influence whether the 11th and 12th Doctor want to free the trapped Time Lords. Was the corruption restricted to a select few (like the President and High Council) or is the entire race guilty of elitism?
Time Lord PCs could fin themselves on either side of the conflict. They could join the Doctor in his crusade, only to find he has suddenly changed sides, or they could be oblivious Time Lords in good standing puzzled why the Doctor is working against his own people.