Your PCs may be ready to take on tougher foes, why not test them against hobgoblins and their commander?

Male Hobgoblin Fighter 3 (CR 2)

LE Medium Humanoid (Goblinoid)
Init +2; Senses Darkvision (60 feet); Perception +0

AC 21, touch 12, flat-footed 19 (+6 armor, +3 shield, +2 Dex)
hp 30 (3d10+6)
Fort +5, Ref +3, Will +1

Speed 30 ft.
Melee +1 Longsword +7 (1d8+3)

Str 15, Dex 14, Con 15, Int 11, Wis 11, Cha 11
Base Atk +3; CMB +5; CMD 17
Feats Power Attack +2/-1, Shield Focus, Toughness +3, Weapon Focus: Longsword
Skills Acrobatics -3, Escape Artist -3, Fly -3, Intimidate +5, Ride -3, Stealth +1, Survival +5, Swim -3
Languages Common, Goblin
SQ Armor Training 1 (Ex), Bravery +1 (Ex)
Combat Gear +1 Longsword, Breastplate, Shield, Heavy Wooden; Other Gear Potion of Bull's Strength, Potion of Cure Moderate Wounds

Armor Training 1 (Ex) Worn armor -1 check penalty, +1 max DEX.
Bravery +1 (Ex) +1 Will save vs. Fear
Darkvision (60 feet) You can see in the dark (black and white vision only).
Power Attack +2/-1 You can subtract from your attack roll to add to your damage.
Shield Focus +1 Shield AC