Cepe, while I disagree with your conclusion, I can see how you've come to it. While it might still be in development, it does seem like you've put a lot of careful thought into it.
HMQs duty is to the people and the monarchy itself and she is making it harder and harder for Charles to be accepted positively as King when the time comes. a 70/80 year old king at the start of his reign creates barriers to acceptance.
The basis for this idea seems to be a common one, but I think it's based on a misunderstanding of the idea of a monarchy. A king (or a queen) is king for life, be that a long or short life. That's one of the key components of the idea as it has existed for thousands of years. Abdication is something that typically has only been done when the monarch is forced to do so. While voluntary abdications are becoming more popular, and may continue to do so as the lifespan of monarchs continues to expand, they are not yet common across the board or even all that common within most monarchies.
Abdications are, by far, the exception to the rule, not the rule itself. Thus, if a monarch is expected to rule for his or her life, it isn't really a vote of non-confidence in the successor if he or she doesn't abdicate. HM isn't saying that she doesn't believe in Charles' ability to rule by not abdicating, she's saying that she believes it is her duty to continue to serve the country. It wasn't seen as a vote of non-confidence when KGVI was struggling with the cancer that would kill him and chose not to abdicate, nor was it a matter of confidence when KEVII insisted on trying to continue to work and refusing to go to bed in his last days, despite having severe bronchitis and having suffered several heart attacks.
There are, of course, cases where the monarch did not have faith in the successor and we can see that lack of faith in their behavior during their reign. William IV suffered from poor health during his reign, but was so adamantly against the then Duchess of Kent that he once swore at a dinner party that it was his intention to live just until the future Queen Victoria 18th birthday so a regency wouldn't be necessary. QV herself had no faith in her successor, and refused to let her Bertie help with the red boxes (while also blaming him for his father's death), and KGV was reported as having predicted that his eldest son would ruin himself within 12 months of his (KGV)'s death.
None of this is remotely similar to the situation with Charles. The Queen is not ill and refusing to relinquish her power. She is not being asked to abdicate by any huge group and refusing to do so. She is not (at least not publicly) speaking about how Charles does not have the makings of a good monarch in him. Instead what she's doing is showing that she does have confidence in him and the future of the monarchy under him, although she does so in ways far more stubble than abdications. Charles is consulted on the red books, he is appointed as HM's representative on overseas tours - notably at the Commonwealth meeting. Last year during the Jubilee celebration there were moments when she stood with just her eldest son and his family, clearly showing that she viewed them as the future of the monarchy. The idea that she isn't showing confidence in Charles by not abdicating only works if there is an expectation that she should abdicate. There isn't, there is no tradition of abdication within the British system so HM failing to do so (especially coupled with a very strong anti-abdication tradition) is not a vote against Charles' capabilities as a monarch.
Furthermore, as has already been pointed out, Charles is not exactly the most popular member of the BRF, nor is Camilla, although both do seem to have come great lengths from their all time low of the 90s. I agree with Vkrish in the idea that the more time and distance put between Charles the divorcee of the 90s and Charles the king of the future the better. It gives him more time to show the public that he is not the playboy he was once made out to be, and that his bride is not the Rottweiler or demon she's been made out to be.
I personally think the more we see Camilla and Charles interacting at events with HM, the DoE, the Cambridges, and Harry, the better and the easier it will be to have the two of them accepted when HM dies. Vkrish also pointed out that HM's popularity does not seem to be dwindling, despite her age. Personally I think that regardless of his age when he becomes King, Charles will shine and be accepted - this is a nation that accepted Edward VII and William IV despite their less than young ages. Sure he might not have the long reign or popularity of his mother, but I think he will be accepted and loved regardless of his age.
It would also clarify the position of the Cambridges and they should be full time royals, learning their craft.
I don't really get the confusion surrounding the current position of the Cambridges. Right now William is the grandson of the monarch, and is working full time in the military. He also has some part-time royal duties. Catherine should not be expected to perform more duties than her husband. William's role is actually more active than the last individual in his position. When George V was simply the Duke of York it was said that he did "nothing at all but kill animals and stick in stamps."
Yes, we'd all like to see the Cambridges do more - and I think it's very likely that we're going to see that happen sooner rather than later, without an abdication - but there is no requirement for the grandson of the monarch to perform full time royal duties, regardless of his position in the succession, and particularly while he is working full time. Similarly, there is no requirement that the wife of a royal engage in full time duties when her husband does not.
There is a lot of talk about the bredth of the royals, but there is also the depth with 3 generations . And that costs a lot more money. And there will be pressure brought to bear on costs and the payment of taxes, particularly the sovereign to sovereign transfer which carries no tax liability.
How would HM abdicating change the cost of the monarchy in any way? Currently the monarchy costs British taxpayers less than a pound per person a year. The monarchy is funded through the two Duchys and the Sovereign Grants. None of that will change with a new monarch.
Furthermore, the number of royals will not change with a new monarch. If HM abdicates then the only thing that really changes is the position of her, Prince Philip, Charles, Camilla, and the Cambridges. Charles will be responsible for paying for his siblings and their children, his parents, his mother's cousins, and his younger son, out of the Duchy of Lancaster. William will provide for himself, Catherine, and Baby Cambridge out of the Duchy of Cornwall.
Actually, if you think about it, HM abdicating would make the monarch financially responsible for more individuals and not less. As it stands now, HM pays for herself, her husband, her three younger children and their children, and her four cousins - a total of 15 people, not including spouses or great-grandchildren. If Charles were to move up without anyone dying, he'd be financially responsible for those 15 people, as well as himself, Camilla, and Harry, while Cornwall (which currently pays for 4 people) would be responsible for 2 people.
As for individuals paying taxes, both HM and Charles currently pay taxes on what they make from their respective Duchies - and at a high rate. Assuming that William will be paying taxes on Cornwall then it makes no difference who the monarch is or who the Duke of Cornwall is, the same taxes will be paid.
If she abdicated, she would be seen the support Charles transition to kingship, there would be a positive response to the Cambridges moving up and the reduction of the BRF would start, at a time when it is needed.
I'm still confused as to how the BRF would in any way be reduced by HM abdicating. This is not a royal family that is established by degrees of relationship to the current monarch - a member of the BRF is determined either by their relationship to any monarch, and maintains that relationship for life or their relationship to an existing member, and remains a member so long as they're still married and/or alive.
The current BRF is the Queen, her spouse, the four children of the current monarch, the six male-line grandchildren of the current monarch, the child of Prince William (by LP), the four male-line grandchildren of KGV, and the 6 wives of the above, for a total of 23 people.
If HM abdicates, then the BRF will be the current monarch (Charles), his spouse, his 2 children, his male-line grandchild, the three other children and 4 other male-line-grandchildren of of QEII, the five male-line grandchildren of KGV (including HM), the 5 wives of the above, and the DoE (by LP), for a total of 23 people.
There is no downsizing unless new LPs are issued to further limit princely titles, which I can't see happening at all during the lifetime of HM. If it does happen, I think it's more likely to happen during the reign of William, after the grandchildren of KGV (who have dedicated a chunk of their lives to the service of QEII) have passed and the non-reigning grandchildren of QEII have all embarked on private lives.
) and gives him even more time to prepare for kingship. 
Forgive me... been up all night lol. Time for bed so that I don't have anymore such slip-ups lol...
