Hey ladies! I need some advice on how tall my centerpieces should be.. this is my inspiration from another knottie..

I'm just not sure how tall of Eiffel Tower vases to use for my 66" round tables. The ceilings in the space are plenty tall so I don't need to worry about that, I'm just not sure how to judge the height so the vases are tall enough to be out of people eye sight while seated but not look overpowering to the tables. Any advice is appreciated.
Thanks!