Each one is a service that passes its tests and still fails in production. Pick one.
The orders page is fast in testing and slow in production. The visible tests pass. Work out what production does that the tests do not.
A page of order history takes at most three database queries, however many orders and products it shows.
Loading a longer order history does not take more database queries.
Orders stay newest first, and every order shows all its items in order, with their names and totals.
A product that no longer exists shows as Unavailable instead of disappearing.
A renamed product shows its new name the next time the page loads.