Unless i got it wrong the upper levels don't make the game harder,as the game mechanics are unchanged. What's different is how the interface info is presented.
From the manual:
Quote:Elite is identical to Warrior with only one difference:
- Enemy infantry icons are always the plain “soldier” type, regardless of their armament or function
So,for example,on Warrior,if you spot a hmg,you'll see the icon for the hmg. On elite if you spot it,you get the icon of the regular infantry.Of course,if you click on that unit you'll know it's a hmg.
Quote:Iron is an optional setting that goes even one step further than Elite, and introduces special restrictions on what the player can do and when. While even more realistic than the other settings, this option introduces a number of interface limitations which might put off the casual player, so it is strictly an optional choice.
- Friendly units need to be spotted just like enemy units. If you have a friendly unit not in line of sight or in contact with another friendly unit, then the only way to find this unit is by either re-establishing contact with another friendly unit or by clicking through the chain of command in the game interface, jumping from unit to unit.
So,as i see it,the game on Iron it's not harder than on Warrior,it only introduces interface limitations which can be easily overcome,but with more clicking,thus more work.