Okay, expansion on the island, more thought that is.
Food/Water: I'm trying to think of a timeline that can work for these, while I find this an interesting mechanic in itself, I'm just trying to think how often would one need to eat/drink in the game, without it turning into something the player will resent doing. In real life person can go a day or two without liquids (I think) And a week without food. So, even with the reduced time frame in relation to game mechanics, what is a good timeline to keep these at? After all, if some people like playing games in one sitting, then either the game itself would have to be stuctured so as to deflect that, or, the time needed between the need to eat and drink would have to significantly reduced.
Time: Another solution, is skip-able time. i.e. like the wait/rest system in Oblivion, this feature in this case would also double as counting as sleep. And means you could justify actually having not eaten for a day etc.
Sleep: So, with the time feature above, there are some other things that could be added to the sleep function. (1) Either another bar added, or, having sleep deprevation be linked to the '
Mental State' bar, and an extra bar, this being '
Energy'. Also, there could be the possibility of weather conditions affecting things aswell. That is, if the player sleeps out in the rain, when they 'wake up' they'll have taken a hit to their Mental State or Energy bars. Or even both.
Energy: This basically how much you can move, how fast, how far. It decreases if you run, jump, or generally exert yourself. When walking it also lowers, but at a reduced rate. Sleep and resting would restore your energy, and there's always the change there'll be certain plants on the island that could give you a short boost.
Plot: This is...Twilight Zone stuff. One minute you're on the plane, the next you're not. I think it would be deliberately ambiguous in this way. Survival is all that matters. And to expand on the physcological aspect. There will be certain points, where the player and the PC 'separate' as it were. Where the fourth wall is seemingly broken, where control is lost, and no longer do you control the PC, but instead become his stalker. This is of course related to the PC's mental state, and may not even be real at all, but it's just to give the effect that the PC is slowly losing his mind. Otherwise. It's you and the island.
Foes: As I mentioned before, there are no guns, but you can fashion makeshift weapons of a sort, using rocks, sticks etc. Now, if you can do this, you need enemies right? But, there are no other humans, except the pilot if he survived. So, of course you need animals. However, these animals, they don't act like animals, they don't make noise other then through their movements and this wierd human like keening. They don't eat, or sleep. They're basically like stuffed dolls left in postions as if they would look in the wild. But they're terribly violent. Any incursion into their personal areas will evoke swift and deadly attack, they can be avoided or killed of course. And yes, you can be attacked when you sleep, there's some leeway here, as the animals will usually let out a scream when they see you.
The Point: I've yet to think on the ultimate goal of the game, does the PC get rescued? Is there some horrific revelation or plot twist? And, beyond survival, what are his immediate goals? After all, although the animals are hostile, there isn't a reason to go out and seek them, as long as you avoid them, you're generally safe. So, maybe, there -has- to be somethig else on the island. Maybe some ruins, deep within that mountain at the center, maybe, of some long dead and twisted, eldritch civilisation. But, I've to think on that.
Would you like to know more?