Another thing to look at on this from a gameplay perspective is what is the purpose of your wall jump? Basically how do you want them to be able to use it. If you make it too forgiving, it can be used to exploit and bypass large chunks of levels depending on how the level design is setup.
What I tend to do with mine is to put the following checks in place and then react with not only Vector Y -someNumber, but to also do some calculations on the Vector X as well. This way when they wall jump, it also forces them out away from the wall they are currently on so that they cannot just continue to wall jump straight up the wall. They are forced to have to jump in the opposite direction which forces the wall jump to be used the way I intend it to, in order to jump back and forth between two different walls or objects. So here is how I set it up:
Condition 1
On Keyboard Right Arrow Pressed
Condition 2
Player Platform has wall to left
Condition 3
Player Platform in NOT on Floor (Inverse of on floor)
Action 1: Player Set Platform Vector Y to -500
Action 2: Player Set Platform Vector X to 400
Then I repeat this for the other directional arrow:
Condition 1
On Keyboard Left Arrow Pressed
Condition 2
Player Platform has wall to right
Condition 3
Player Platform in NOT on Floor (Inverse of on floor)
Action 1: Player Set Platform Vector Y to -500
Action 2: Player Set Platform Vector X to -400
Of course adjust your X and Y vectors to meet your specific requirements, but the point of mine is to push them far enough away from the wall they are currently on so that they cannot curve back to the same wall and jump off it again from a higher spot. Effectively keeping them from just jumping straight up the wall as much as they want, because that takes no skill.
Instead it pushed them up and away from the wall with enough of an angle that if there is another wall nearby they can then jump off of it to come back to the current wall. In effect forcing them to jump from one wall the other and if they are going to continue to go up, they will have to continue to switch walls with each jump. Basically making a zig zag pattern of jumps between the two walls.
Just food for thought, wall jumps are a great game mechanic, but you have to really be careful in how you make them function or they are easy to exploit and remove the challenge from a game.