Guild Wars 2

As above. We’ve currently unlocked every guild mission type. Post HoT will we need to go through another rigmarole/grind etc to unlock them all over again?

No, after HoT guild missions will no longer even need unlocking. There will be other things that you’d likely want to work on (number of slots for missions, for example), but mission types themselves will no longer be locked beyond guild upgrade levels.

(from what i can understand, the guild mission activation consumables will get obsoleted as well)