** I'm wondering if it's not better to let every inch of the pedestal rest on the floor **
Definitely. The more contact with the floor, the better the chance of it withstanding the forces during a wash cycle without vibrations and movement. If it is a front loading washer model, stable flooring is absolutely critical to the machine's operation and longevity.
** and simply adjust the "feet" of the washer and dryer for balancing. **
That will depend on how much they need to be screwed out to make them level. The washer's feet should be kept screwed in as close to the cabinet as possible for best stability of the appliance.