Obviously, I haven't played the game, so maybe the zombie killing and story missions aren't good enough for higher praise and scores. but when these reviews say "just zombie killing and story missions", I wonder what else they expect, let alone from a Dead Island game. Wasn't the new hotness to say that games need to stop being bloated with endless fluff and side content?
And we wonder why games take so much longer to make these days. It's not the only reason, but apparently fans and critics alike want every game to be everything and an extra drumstick.