I believe there should be a mod for both X-COMs that list difficulty levels as the following:
Rookie - Beginner
Sergeant - Experienced
Captain - Veteran
Commander - Genius
Scourge of Aliens - Superhuman
I also would like to see a mod for TFTD that adds a new armor
Diving Armor: purchasable from sponsors, diving armor is an improvement over the diving suit but is not as strong as other armor types. It is made of the best earth materials and can occasionally mean the difference between life and death on the field.
Armor Values:
Front: 30
Sides: 25
Rear: 20
Under: 20