Frankenstein 6 - Frame Story Cont'd

I have just discovered the drawbacks to the frame story technique. A frame story allows you a glimpse of the resolution of the story and offers a limited scope for the imagination. Specifically in Frankenstein the frame story structure lets the reader know that Dr. Frankenstein and the monster end up in the North Pole. With this knowledge, it is aggravating trying to imagine an end to the story. I have a hard time filling in the gaps between the inner frame story I know and the outer frame story that has not yet been completed. I wish I was able to imagine my own end to the story, instead I am going in circles trying to figure out what events unfold between the two stories I already know.