Right now, it's hard to track the history of which questions have been used on the tour page. It's not possible to know when someone selected a question for the tour page and who, and when it was removed and why. In case an inappropriate (e.g. bad "showcase") question is selected for the tour, one can't know who was responsible for it and for how long it was on the tour.
Also, when a question that's currently on the tour later becomes ineligible for selection, which can happen through several factors that don't involve it being bumped (e.g. through comments being removed or through the author deleting their account), no one is notified, so it's extremely hard to tell when it became ineligible and for what exact reason, and for how long the generic "unicorn" question was showing.
Can a history event please be added to a question when a moderator selects it for the tour page, and another event when it's removed for any reason (e.g. through a mod changing or removing it, or it being removed by the Community user if it becomes ineligible)? This will also make it so that the community can implement an alert to notify mods in case the tour ends up automatically reverting.