I originally put a vase of flowers on the dinner table, but then I removed them because my sister-in-law stated that they were too tall. In thinking more about this, what should I have done?
If the centerpiece interfered with your guest's view of each other, then the vase of flowers was too tall. However, you could cut the flowers and place them in bowls of different heights. Also flower blossoms floating in shallow containers make lovely centerpieces.
One general rule-of-thumb is to keep centerpieces below eye level or less than 12 inches tall. Exceptions to this rule are very tall centerpieces such as helium balloons.