Goblin Trapper
This little guy is more of an excuse than a real monster. Usually he will be in the back and retreat first once fights south. The most common trap will be a pit fall which is easy to construct and not that deadly. On forested trails they might employ spring snares. Those two are the bread and butter for a Trapper. They are relatively easy to set up but for calculations sake we will say that a goblin trapper will have a band of at least 9 total goblin with 7 average ST and all have wooden tools. Using the Basic Set digging times our team of Goblins can dig 2 Cubic Yards per hour, meaning in 2 hours they could have turned an ordinary hex down to a respectable 4 yard drop. Snare spring traps are an easy 30 minute set up but cover less of an area, and since the party will be traveling together it won't be much of a setback unless it's followed with an immediate ambush.
Goblin Chaff
The rank and file of the goblins, the cannon fodder, the monster you send out when you want to make your players feel like a badass. It doesn't work too well since nobody feels that good after turning a goblin into a red paste. Goblin chaff are only a problem in the most dire of situations or when ambushed by them. When ambushed they should flee immediately or surrender in case they can't scram in 50 different directions. They should often be armed with spears, clubs and simple bows. If nobody is there to command the goblin archers they should not be aiming at all and shoot as soon as they are ready.