Manchu wrote: the good guy side of things is pretty much a wash. Getting that many characters into a list is certainly possible under the rules but it would be a ton of points. The goblin side has the opposite problem, goblins are super cheap.
In terms of using the models outside of the scenarios/campaign -
Thorin's Company has a special rule that allows them to be fielded as a standalone army in normal games of SBG - though it is hard to play as you will be outnumbered and often outmaneuvered!
The Goblin-Town army is pretty fantastic as an evil army. 400 some points and a totally legal army, as it has enough heroes and warriors to field as such!
And, of course, the terrain is fantastic.
If you enjoy playing the scenarios from Escape from Goblin Town (and the main box also has scenarios for the rest of the first Hobbit film as well, with hunter orcs and whatnot), you can get There And Back Again which has more scenarios for the second and third Hobbit films, set up in the "journeybook" style - models you build and paint and use in previous scenarios almost always get used again in later scenarios.