Brilliantly comprehensive, I have nothing to add.

Except perhaps, as a tangent, I tend to not book flights too far in advance in case my plans change, even if paying a little more sometimes. There can be a temptation to chase a better price, but you may lose flexibility. Of course, you can cancel, but those fees are huge or sometimes the wrong tickbox selected means you can't even cancel.

This idea - only paying for what you are certain to use - reminds me of gym memberships. I was told by a manager that they make the majority of there profits not from running the gym for visitors, but from running the gym for the non-visitors who intended to visit. Unless having a track recording of attending in the past, as much as you plan to in the future, then use one-off visit payments until you have proof of your actions!

- Manlobbi