2. A Helghast campaign

That's right, we said a Helghast campaign. Let's be honest, the ISA and its soldiers aren't the most memorable of characters. It's not like you really care for them. And, actually, it's the Helghast, with their emotive red eyes, gas mask-altered cockney voices and incredibly realistic hit animations and AI that steal the show. So what we really want is more of them, not the generic marine Sev and the ISA. What we really want is a Helghast campaign that shows things from their point of view: an existence dogged by hardship and endless conflict, and reveals the uncomfortable truth behind their origin. This campaign, along with an ISA campaign, could be weaved into each other, perhaps even meeting at some point towards the end. Think Halo 2 but better.

1. Co-op

We can't think of any one thing that would make the core Killzone experience better than co-operative play. We're not just talking about two-player split-screen here, either. We want a full-on four-player co-op campaign, playable online over PlayStation Network. Imagine being able to co-ordinate flanking attacks against the Helghast, or indeed against the ISA, with your mates via a headset - two players could lay down suppressive fire while the others inch their way towards the enemy's vulnerable sides. Imagine having two players driving two separate vehicles, the other two manning weapons. Imagine a Gears of War 2 Horde-inspired mode, except with 16 players working together to survive the waves of Helghast? Co-op play would open up Killzone 3's options immeasurably. Make it happen Guerrilla, and we'll love you forever.

What ideas have you got for Killzone 3? Let us know in the comments section below.