Don't: give me a mounted gun that points back at the path along which I just ran, killing everyone by hand. This seems to be the absolute default now. They only serve one purpose: finding out that they didn't bother to make the scenery destructible. Let me play with a mounted gun! Unless it's a sequence in which you force me to use a mounted gun, probably on the back of a truck. Stop that.
Do: agree to an industry wide standard on the location of save games. Save games are not a secret. They are not a treasure. They're something most right-thinking people want to be able to preserve after a game's uninstalled. They're something many people need to get at when building a new machine, or simply continuing the game on another machine. They aren't a DRM risk. We just want to know where our save games are, and we don't want to have to trawl through seventeen different possible locations in the very bowels of Windows, trying to discern which lunatic name you've filed them under. When I install a game you let me choose the install location. Can you guess where I want the save games to go to? Here's a hint. It's not in C:\Users\John\AppData\Local\Roaming\Documents\Programs\Features\Gardening\Knitwear\Publisher\Developer\GameName\Sausages\X34265\
Don't: stop me from sprinting after three seconds. Look, look at me. I'm a fat man. I can sprint for more than three seconds. I can keep going for a good... four seconds. Before collapsing on the ground, red, sweating, pleading for the ambulance to offer me oxygen. But the character in the game? Lean McBuffington? He's made entirely out of muscles. He's a man who can sprint. Since it's apparently possible for us to jog absolutely everywhere, maybe we can run further than from the living room to the downstairs loo. After all, games are supposed to allow us to live our dreams.
Do: let me move during cutscenes. I know, you want to make film, and life gave you videogames. But videogames are amazing! You don't have to sit passively in front of the screen, having the prescribed script play out at you as you sit nailed into a chair. Let me wander around! Let me jump on the tables, or spin on the spot. Let me see what objects can be picked up, and try to pile them on a key character's head. Let me run around them in maniac circles. And you know what? Letting me look around but not move - that's actually worse than taking away my controls entirely.
Don't: splash on my screen. I AM NOT A SCREEN! I'M A HUMAN! When it rains, this does not leave droplets running down the front of my vision. This is because I have a face, including a nose, chin and forehead. Concealed between these features are my eyes - two orbs that sit within the protective bonage of my skull, accompanied by the cleaning and dust-deflecting skinflaps of my eyelids. Were raindrops, or worse, splatters of blood, to become visible droplets in my vision, they would have to be on my eyes. I would respond to this by running around, screaming in pain and fear, clutching at my face and begging for help. You appear to be under the impression that I am a sentient monitor. Perhaps a screen mounted on top of human shoulders. I'm not one of these. I'm reasonably sure the character in the game isn't one of these. So just perhaps can we please stop having splashes appear in front of our view? (Oh, and I'm also not a bloody camera lens, so can we also get rid of lens flare too? Kthnx.)
Do: let me kill my friends. Sure, it's a game over. But let me! I've got a gun. They've got a head. When the gun refuses to fire at them, well, perhaps you can argue some astonishing technology that recognises non-enemies and forces the safety. (If you could work on inventing this for the US army, that would be awfully helpful.) But when bullets and chairs bounce off them without comment, you've somewhat spoilt any notion of fiction you may have tried to establish. Also, if they get to be invincible, how come I don't? I'm on the same side! So yes, it's a game over, but let it happen.