If i were to shrink the image i would do the following:
1. Mount the partition that has the most extra space under some folder
2. Tar the contents into a tarbal, (remebering the -p option)
3. Unmount the partition
4. fdisk the image and remove the partition
5. create a new partition with a more suitable size
6. create a new filesytem on the new partition
7. mount the new partiton under some folder
8. uncompress the tar backup (remembering the -p option)
🙂