MortalPlague
Adventurer
Looking at the party, it seems pretty melee-heavy. That sort of group can be tough to challenge with raw damage. I'd look at using some ranged artillery and controllers who slow or immobilize, combined with a few tough guys on the front line. Not too often, mind you, but once in a while to expose the party's weakness.
On the topic of MM3, I have it, and it's great. There are some amazing monsters in there, especially at and around the level you're hitting. Also, Greg Bilsland (one of the writers on MM3) has an excellent blog, where he talks about the adjustments to monsters. His quick fix; double the static damage a monster deals (or triple it, if it's a brute). So if a monster does 2d6+5, make it do 2d6+10 (or 2d6+15 for a brute). Also, give brutes a +2 to hit; the penalty to their accuracy isn't doing them any favors.
Finally, and you've probably heard this, but it's important to keep in mind; let the players win. If they're having fun rolling through encounters, you're doing something right. It's great to challenge them, but if you make every encounter a slog designed to leech their surges and shut them down, you risk losing what makes your game fun. I think we're all guilty of this from time to time, so it never hurts to keep the fun of the players in mind.
On the topic of MM3, I have it, and it's great. There are some amazing monsters in there, especially at and around the level you're hitting. Also, Greg Bilsland (one of the writers on MM3) has an excellent blog, where he talks about the adjustments to monsters. His quick fix; double the static damage a monster deals (or triple it, if it's a brute). So if a monster does 2d6+5, make it do 2d6+10 (or 2d6+15 for a brute). Also, give brutes a +2 to hit; the penalty to their accuracy isn't doing them any favors.
Finally, and you've probably heard this, but it's important to keep in mind; let the players win. If they're having fun rolling through encounters, you're doing something right. It's great to challenge them, but if you make every encounter a slog designed to leech their surges and shut them down, you risk losing what makes your game fun. I think we're all guilty of this from time to time, so it never hurts to keep the fun of the players in mind.