For those who want something more powerful, there is KdenLive and Shotcut. For in the middle between avidmux and kdenlive/shotcut there is openshot
Da Vinci Resolve Free. That is not only a professional video editor but much more with colour correction, video stabilization, compositing, sound editing and effects. Exports directly to youtube, etc.
Thanks for the recommendation. I've been using Handbrake but really could use the more fine-tuned cutting. I always like a lightweight option with GPL licensing.