My vote would be for Mxyzptlk or Bizzaro… I think a solid writer could make us readers cry, gnash our teeth and pull out our hair over either of their deaths
Sinestro. Done as a slight anti-hero and this could be epic.
Mr.Freeze finally allowing him to be at peace and with his wife would cause me to need the tissues
Probably Hush (Tommy Elliot).
Eobard Thawn… his time has run it’s course.