Man, this one right here hit me "right in the feels."
Donatello's innocent expression is endearing despite the pitiful situation.
Also the care and patience Leonardo has to care for him every day, feeding him the soup, pushing him around the park, and pulling him up into the sewer tunnel.
On question I had was the nature of the world the old Turtles inhabit. Do they still wear disguises in public and live in the sewers for protection from the human world or is it just their preference? I like the idea of a future not necessarily being apocalyptic, despite some obvious losses and uncertainties.