Lol I was waiting for someone to post before i fell asleep
If I may chime in. If the first arc is based around Sithilerin. I had an idea about a person who is spreading death and corruption through the forest. This individual knows that the forest can't be corrupted completely without Sithilerin's death. So they hire the bandits you are talking about. They get their asses kicked first but maybe find out that a part of Sithilerin's great power is because his soul is tied to an artifact called the "seed of the first tree". An artifact that grants nature it's life. So then they set out to steal it and are barely successfull. So then the evil individual tries to corrupted it and Sithilerin recruits our friends to help him stop da bad guys.