In Camp Nightmare I initially designed cards around two styles. Either the card helped everyone, like Saw, or it just helped you, like Axe.
All players gain +3 Wood when they Gather Wood.
You gain +4 Wood when you Gather Wood.
The thing is I want this game to work with any number of players from 1 to 5 so Axe wasn't really going to work as is. In a 5 player game you would often not get to use your own Axe before it got trashed anyway and at most you would get a single use out of it. To get around this I introduced the concept of Borrowing where players would pay 1 Energy to use someone else's equipment for a turn. That worked out all right but it ended up being a serious balance concern because games with a lot of players poured *tons* of Energy into Borrowing and everyone had to keep track of which items were universal and which were personal. It worked, but it was clunky.
I decided that a different approach that wasn't so strongly based on number of players was in order. The new design has gear that just helps you but it does so based on what other people do. Essentially you have selfish gear that doesn't diminish in power based on how many players are in the game, like the Hammock below.
When any player Naps you gain +3 Energy.
This way you can actually use cards that act on you personally and forward your own strategy without worrying that you won't get a turn to use them. Of course your allies will need to work with you and take the Actions that activate your gear but the game is a cooperative game so that makes sense. Of course a lot of the cards are more complex than the examples give above and take a form more like the Flashlight or Camp Chair where they are a hybrid between selfish gear and group gear.
When any player Rummages they gain +2 Energy and you draw 2 cards.
All Food cooked on a Fire gives +3 Food. You gain +3 Energy when you Nap.
The new design has the pleasant side effect of removing the need for the concept of Borrowing completely. I take great pleasure in hacking out chunks of the rules because one of the signs of a good rulebook is brevity. Take everything out that can possibly be taken out. The easier it is to get new players in to the game and the less that needs explaining the better your design is.