There is no sense of events happening around you the game just presents an infinite sandbox for you to run around in. It doesn't have a story - And what story it has lacks urgency and punch and character Where MW4M had you run around the Inner Sphere, visiting defined planets that each had their own little mini story arcs that fed into the overarching FedCom Civil War storyline that the game was set in, in this game, you are running around the IS taking generic contracts from characterless mission givers which tell no story.
This game lacks a lot of what I want from a modern MechWarrior title. It does the Oblivion thing of having one big voice actor right near the start (Elias Toufexis, in this case) to lure you into the idea that there is more to this game than there actually is, but.