I think it's fair to say that I'm very fond of open world games, from the balls-out fun chaos of Just Cause 2 to the carefully-planned surgical strikes of Assassin's Creed. It seems like the sandbox is the only thing that really makes the most of what triple-A technology is capable of, in gameplay terms at least. I mean, creating a nice mountain scene as a backdrop for your shooter doesn't have the same appeal if you can't then climb to the top of the mountain and detonate enough explosives to have it re-classified as a hill.
But in the aftermath of Sleeping Dogs I have identified a number of recurring issues with sandbox games that could be rubbed out with a little more thought at the design stage. Specifically, that number is two. I have two issues. Here is the first one.
1. A lack of coherent timekeeping
It's no new observation that there's a rather drastic discrepancy between the story missions and the open-world gameplay in sandbox games. This is best illustrated by the fact that, in Sleeping Dogs, Wei is only truly inducted into the Triads after he's proved a willingness to kill within a story mission, even if he has been busily shoving people into bandsaws and crushing their heads under engine blocks throughout side missions up to that point. GTA-like games have historically gotten around issues like this by making the main characters obvious amoral sociopaths like Tommy Vercetti or Niko Bellic so that nothing the player does to amuse themselves between missions seems inappropriate.
But an important part of linear storytelling is having a sense of what kind of timeframe the game's story operates in. Going merely from game play time it might seem like Wei rises to become the leader of his particular gang within the course of a weekend, but it's implied that all the free-playing you do between missions is actually representative of anything up to several months, even if you go straight from the last mission to the next. I think this is a failing of sandbox storytelling because having a firm grasp of the timescale is important to things like characterisation: someone working at their quest for years comes across as far more determined and tragic than someone who's been working at it for a fortnight.
Did you know that the story of Assassin's Creed 2 takes place over the course of 16 years? Ezio's family is killed in 1476, and the final confrontation takes place in 1492. But this timeframe is made very unclear by the in-game events. Occasionally it flashes up the year, but unless you made a point of memorising the previous 4-digit number, it doesn't sink in very well. I always felt that the simplest of changes here would have made a vast difference: all they had to do was replace the year reminder with a relational statement like "Two Years Later", and it would have given a much clearer handle on the timing. The faintly ominous "One Year Later" chapter break screens in Grim Fandango gave a very coherent sense of the game's epic scale.
Alternatively I always liked the Dead Rising approach where there's a strict in-game clock and events only become available within certain times, but that probably wouldn't suit a story taking place over weeks or months or years. No-one's going to keep their consoles on that long.