Thanks for those pics!
I wonder if the Micra has an "Achille's Heel" when it comes to rust.
Some cars have problem areas that doom them to an early grave because of corrosion in structural areas. Two examples: the Toyota Echo, which had a fatal flaw in the area where the rear axle attaches to the unibody that trapped dirt/water and would make them unsafe. The Suzuik Swift/Firefly/Metro had a similar flaw in the front unibody at the lower control arm attachment point. Repairs to either car were too expensive/complicated, and lots of them went to the crusher while they still had lots of life left in them, mechanically.
On the other hand, I see a LOT of 20+ year-old Tercels in my part of the world -- those cars are the cockroaches of the economy car world from the 90's. They may be rusty around the edges, but clearly they don't suffer from a fatal flaw in terms of corrosion.
Unfortunately, we're not going to know about the Micra's problem areas until the cars are a bit older and we start to see some rusty ones.
View my fuel log 2015 Micra S manual: 5.0 L/100 km ... 56.5 mpg (Imp) ... 20.0 km/L ... 47.0 mpg (US) ...