evilbob
Adventurer
Aside: I have to say that this post has the exact opposite effect on my own opinion of the warlock; I considered the class to be extremely underpowered, especially at higher levels, since throwing around 1 shot per round with an average damage of about 30 is basically nothing compared to a fighter with 4 attacks that cause massive damage checks every time he hits! Sure, at low levels having consistent damage (warlocks don't really miss) is great, but by level 6 he's already way behind the damage curve. Add to that the fact that many of his natural abilities seem to be predicated toward avoiding damage (which, as a ranged fighter, he shouldn't be taking much of), and you have a rather peculiar class. However, being able to use his (optional) shattering ability against much more than mundane weapons (which you never see after level 6 as well) is a great idea and makes him a much more useful class! 
To respond to the OP, however, I would advise against changing the class in any way, or even asking the player to change his playing style. I wouldn't even alter the XP rewards, either. The truth of the situation is: he's actually just doing a really, really good job of playing his character. If his character seems to shine too much, then it's your job as a GM to make sure others shine in turn. I'm sure you can still come up with good ways to slightly alter pre-made adventures to take a little bit of the "sheen" off his character. For example, large doors with hidden or built-in locking mechanisms (still need line of sight to target something, and you can't shatter very heavy objects) could solve your "trap avoidance" problem well. This probably isn't the answer you were looking for, but IMO you'll just need to be more creative!

To respond to the OP, however, I would advise against changing the class in any way, or even asking the player to change his playing style. I wouldn't even alter the XP rewards, either. The truth of the situation is: he's actually just doing a really, really good job of playing his character. If his character seems to shine too much, then it's your job as a GM to make sure others shine in turn. I'm sure you can still come up with good ways to slightly alter pre-made adventures to take a little bit of the "sheen" off his character. For example, large doors with hidden or built-in locking mechanisms (still need line of sight to target something, and you can't shatter very heavy objects) could solve your "trap avoidance" problem well. This probably isn't the answer you were looking for, but IMO you'll just need to be more creative!
