'The tradition is that the head of Magical Law Enforcement would be the acting minister' -- interesting idea, but could you really see Fudge as head MLE?
'I will be inviting them here to the headquarters. It will be much safer for them here' -- ? Albus just got finished saying the Order would have to move to Hogwarts because the building might belong to Bella or Cissy, why then would it be safer for Susan and Neville?
Author's response
As for the head of MLE being acting Minister, there is no reason why Fudge should have been acting Minister at any time. Fudge was the regular Minister who was elected via whatever Wizarding elections there might be. You do not need to be Head of MLE to stand for Minister elections - it is only in times of crisis and there is no Minister for whatever reason that the Head of MLE acts as the Minister temporarily.
As for Neville and (as Dumbles imagines) Susan, he will move them to Hogwarts when the others move there. Albus' point is that they are safer with the Order members rather than staying alone (or with anyone else, for that matter - Albus strikes me as the kind who would be satisfied with only his own solutions). But thanks for raising that point. It is a very interesting and pertinent remark you made about the Order. I will clarify what Albus had in mind.
Thanks for the encouragement and thanks for reading and reviewing.
Regards,
Maidros