The Oblivion games try to do it, but that is one of their biggest weaknesses. Players just get lost and ten hours into the game they’ve realized they’ve done nothing productive in regards to the main story and quit.

But I don’t think escaping linear progression should be the goal of every game, or even most games. It’s a valid design choice that can help make experiences focused and intense where used well. The gameplay of Half-Life has never really been about exploration or sandbox-play, and inserting that kind of action into the proceedings would only take the spotlight off its real strengths in scripted sequences, character animation and individual-vs-squad gunfights. (In fact, the sin of Half-Life 2 is that it doesn’t play to these strengths nearly often enough – again fixed in the sequels.)

I realized years ago that, while I like the storylines, etc. in some RTS games, I hatehatehate playing for 30 minutes or an hour and then getting ripped apart for a bad build choice that I made 5 minutes into the level. FPSes are, by their nature, linear, and generally the best way to make them linear is to create only a very few paths with a few fake crossroads where people will be funneled to. The other option is to go the MMO route, and have the enemies outside of the area the player’s supposed to be in be almost impossible to kill with the weapons currently available to them, and that’s frankly just not usually as successful.

I’m not saying criticism of the genres doesn’t have its place, but the most compelling way to tell the story in a FPS is generally the one that’s been glommed onto by most developers. Maybe later someone else can come up with something that is both compelling and cost-efficient, but I’m not holding my breath.

Bioshock got away with a choice of ethics which marginally changed the gameplay, but the plot remained the same, either way, and the objectives were clear and linear. It added a bit of phantasm (that quality wherein your effect upon the game affects you) to the experience. Because of the minor effect of this choice upon the storyboard, length didn’t suffer.

Oblivion offered a sandbox. One could do pretty much whatever they wanted. On the other hand, combat was very simple and formulaic. There wasn’t much of a choice in character development unless you wanted to cripple yourself for a challenge by not being a fighter-mage-thief. Some of the quests were interesting, but most were rather static. “Level” design was atrocious and as repetitive as Hellgate London turned out to be. Sandboxes sometimes have tiny areas of polish, but for the most part it’s rough as sand.

Shooters are made to be cinematographic. Some freedom is always welcome, but add too much and you lose focus. For other types of gameplay, play sandbox mmos. Don’t insist muffins are bad just ‘coz you like cakes, mkay?

By contrast, I liked the panic and adrenaline of Doom 3’s monsters who lurked behind corners and shadows – though the repetitiveness of the level design has kept me from finishing the game. Intend to get back to it some day though.

The FPSes I did finish were those that were linear, and didn’t make excuses about it because they had some kind of story to tell. (Having a unique atmosphere helps too.)

FEAR – a mystery that needed answering, and lots of horror type suspense.

Bioshock – underwater dystopia, with discovering the protagonist’s story as its goal.

Call of Duty 4 – Modestly named, for something that totally embraced a cinematic action thriller style, shamelessly going linearly forward…but it was so intensely movie-like that I didn’t really mind.