I'm not sure if this has been stated before, and I apologize if it has (nothing came up in a search), but what about breathing? There are limitless amounts of planets, right? Well what if each planet had a different amount of oxygen requiring certain items to be used? (space suit, oxygen mask, etc) This could change from lower level planets being able to breathe fine, and higher level planets need a space suit or something of the sort. Maybe our tech guys in the space station could come up with a chemical pill or something to allow our bodies to require less oxygen..
I thought about that too. It would be a great addition and an additional hazard on a planet to make the game harder. Overall there should be more environmental hazards, that influence the gameplay.
Further, perhaps some planets could have a toxic or corrosive atmosphere, requiring them to be explored in a vehicle or mech. And the other way, some planets could be surrounded by an EMP field and can only be explored on foot.
I'm glad to see some people are interested in this idea. Maybe there could be some creatures that could spit/breathe certain gases at you. Or maybe these creatures, once tamed, could remove the dangerous gasses from the planet like how trees make an oxygenated atmosphere.
This kinda goes with my weariness thread c: have a look at it http://community.playstarbound.com/index.php?threads/weariness.1102/
I really like the idea of work causing that meter to go up faster. The more work you do, fight, build, etc. would cause your oxygen level to deplete much faster. This would add the need to use caution and careful planning when visiting those dangerous planets.
I know this doesn't match to this thread, but how about I throw in the idea of a food meter, if that hasn't been said already! Or, another idea would be, eating food to restore your weariness, because I like that idea!
I would be more open to weariness if there was a recovery item I could use to cure it, not just go back to the ship and rest. Combining these two ideas could work great!!
Maybe the devs could implement a "realism mode" for different pace. I can see some people complaining about too much realism, but if it was implemented in a game mode, maybe attached at character creation, like hard/med/soft-core modes, this could add a layer to the game that many people could find interesting. That way it could keep the non-realists happy, while keeping the people looking for a more realistic challenge happy as well.
Having different game modes could potentially multiply the game time. Eg. 6 different game modes = 6 times the amount of gameplay.