Well, getting a high passive perception is not difficult in 4E, which means most groups will include at least one character able to find almost any trap.High passive perception should find almost any trap.
Or something with pull powersIn what way is a trap that you do not find interesting? There is no challenge, just random damage. You might as well institute a random damage table and no wand then. A trap that is discovered still has to be bypassed, that's where the challenge lies.
Besides, in 4E, traps are supposed to be part of encounters. Even a completely open and obvious pit trap can be trouble when there are archers on the other side.
And that's fine. The purpose of a trap is not to go off. It's much better when the characters notice the trap and then have to take measures to disarm/circumvent it. Otherwise it's just "damage from nowhere".I wouldn't want to punish a player simply for having a good score in a skill.
The problem is that some characters can have such high perception skills that they'll effectively never fail to detect a trap that falls within their level range.
Make the trap "attack" his passive perception. In other words instead of having a trap with a Perception DC of 20, it has a Perception attack of 9 (subtract 11 from the DC). When the times come, roll the attack for the trap. If it hits his Passive Perception, he hasn't noticed it. The character is still rewarded for having a high perception.
And that's fine. The purpose of a trap is not to go off. It's much better when the characters notice the trap and then have to take measures to disarm/circumvent it. Otherwise it's just "damage from nowhere".