Marge is not stupid, she has to freeze out Marie, no matter how attached she is to her because if Marie and Mary are in the same events too often, a lot of people might notice that Marie would also make a lovely Queen
. Same goes for Jokke - someone might notice that he is King material (at least better than his brother).
I think they don't want to create a Swedish situation with crown princess + shadow crown prince (CP). A lot of republican Swedish people might fear if there are five royal children they have to feed in future (Victorias and CPs) - in the case of the DFR that would be eight children in the next generation, if everyone was a "professional royal".
When Vic was born the change in inheritance legislation was already under way but clearly nowhere near being finalised. CG had an expectation that a boy born as CP would not be stripped of the title etc ... ie next generation. It did not happen. As for Marge ... Fred was born CP and nothing would change that .... luckily for Denmark his first child was a son. So anay issue of a daughter being recognised over a son is decades away.
Would Jokke be "better" ? With his health issues he is better off in private life