It's not my idea, but it's one it was interesting last year to follow through on and for a bit of fun that I've copied in here (also I get to show some Robert McGinnis artwork, and he's the poster artist of my childhood).
If we assume that 'James Bond' is like 'M' and 'Q' a code name only? We start with Sean Connery, possibly the first, possibly actually James Bond. The name becomes powerful, fearful. He rarely after all hides it.
Bond however goes out of contact whilst in Japan, at the end of You Only Live Twice he is still on Blofeld's trail and refuses to come in.
But SIS need 007, and they certainly need 'James Bond', and of course by now their famous agent cannot be tarnished. They get a lead on Blofeld and even in the film it starts with M and Moneypenny discussing where 007 is. So they have to come up with a plan, and they come up with a stand-in James Bond. They don't choose a proper sociopath but one already involved with one of villains, Draco's daughter (actually, Emma Peel). All in all it does not work for the best. Tracey dies and their stand in Bond goes to pieces. It is clear that 007 really does need to be a thug, they do need the real James Bond after all.
Which is why all is forgiven and in Diamonds Are Forever when contact is made M will put the name Blofeld to any villain to keep Bond in line, and Bond will make much the same assumption. By the beginning of the film they are in uneasy alliance - even though Bond is borderline insane (murderous bastard quite aside).
At the end of the mission Bond vanishes with Tiffany Case - and a fortune in diamonds. Maybe it was M that tried to have Bond removed through the independent Wint and Kidd? Either way, Bond is firmly gone and
All would rest until three British agents are killed - and links are made to Kananga. SIS fight fire with fire - they need their own 'Loa', their own legendary agent of death, James Bond. The Roger Moore character is made the new Bond and the new 007. And despite all is brutally efficient, and for many years and missions thereafter. To the extent however that in the end he is actually awarded the Order of Lenin (View to a Kill) and aging now leaves the service honourably to marry Stacey Sutton, the oil heiress. No hard feelings here. 'Bond' served his country and there is a new wind of detente. During this period M passes away and his brief replacement (importantly) rubber stamps the Bond programme - making it official.
A defector is set to do that and SIS set a counter sniper in place - one who shows resolve but a streak of judgement when he does not actually kill the woman assassin. The newly promoted M (Judy Dench) sees something in that man and when that man (Dalton) is trained up to be a 00 then on his final training mission others are killed and he survives on Gibraltar M makes the judgement that this will be no normal 00, but 007 James Bond. Never comfortable with the idea of SIS having an assassin she had been quietly keeping 'James Bond' vacant, but her hand is forced. For the first mission this works admirably, old elements of Smersh are suitably distracted by the their 'old adversary'.
The new Bond though is not perhaps all he should be. On his next mission he resigns - indeed his Licence to kill is revoked by M (who had been looking for just such an excuse). The film is not so much about James Bond as what happens when one in that position walks away.
About this time two 00s are in Arkangelsk, Brosnan and Bean. They blow stuff up. They are 00s but neither is Bond.
Six years later and Brosnan is made up to 'James Bond'. M has hardened. if she must have a Bond, it will be one of her choosing. For the first few missions it seems they finally have a Bond back. One that gets the job done, is ruthless, efficient and everyone is pleased. But he is flawed, he is not the sociopath that the original was and he is forced to retire to lengthy treatment when he starts to think that John Cleese is Q and that his car can turn invisible - the poor soul goes barking. M's demands for a more balanced figure, a trained assassinis shown to be flawed after all.
And then and now a new Bond. Hell, Casino Royale actually shows the early process. M is visibly nervous at the latest result of the 'Bond' programme established by her own predecessor but 007 is now like a tiger on which she rides. It's dangerous, but more so perhaps to get off.