I think we can all agree that the game could have, and would have been better had it not been for the deadline that was forced on them, major gripes beeing that the zone is not as big as it could have been, and the A-Life consept has been replaced by way too much scripting.
But the biggest gripes for me can be summed up in 2 points:
1) the "GTA-syndrome", here we have this great big zone, we want to explore it! but we dont get to do so untill we have finished about 2/3'rds of the official missions, places are locked, or just plain suicide to wisit untill you have compleated a bunch of missions or aquired some needed gear that you can only get from missions.
You really have to play by the numbers untill you are allmost at the end before you get any real freedom.
2) the missions wont leave you alone, any time you wisit the Garbage for instance, you get the same pop-up missions, defend this camp, defend that one, destroy this one.. and thats a real pain when you are allready on a mission! more so because you will fail thease pop-up missions if you dont come back and collect a reward within a day (WTF!? he owes me money for work done, how can there be a timelimit on that?).
Likewise double and tripple missions are annoying, i go to steal a briefcase, but before i can i am presented with a bunch of missions i cannot say no to, by the time its all done, i only just have time to hurry back and collect my rewards before they run out of time (and now im carrying a ton because i found a bunch of unique items that can only be gotten here), so i have no time to explore.
It all ads up to the same thing, we want to explore the zone, we want to find cool places, hunt for artifacts and unique objects, find the stashes, but we are not allowed to, its locked, you dont have the time, or its a suicide run, so you really cant do it.