A nice touch is that the difficulty setting can be changed from mission to mission. In addition, the easy setting is exactly that, easy. I was able to replay the entire original campaign from scratch, and if a mission got too dicey I could gear down the difficulty to easy and breeze through it. This new freedom allowed me to replay the original campaign with a much higher level of enjoyment as well as enjoy the new campaign based on my personal preferences. Desperate Measures also offers a number of play enhancements.
Players can take advantage of a number of new keyboard shortcuts.
The real boon to play though is the ability to set waypoints and conserve ammo. One of the big peeves of the original release was that the opening movie showed what looked like waypoint movement, which the actual game was devoid of. The ability to conserve ammo by only firing weapons with unlimited ammunition also gives renewed usefulness to the ability of setting forest fires and taking out walls without wasting valuable ammo supplies. The game also tweaks the ability to aim shots. In the original release aimed targeting was ludicrously difficult.