Wedding Centerpieces for a Friend

I'm helping a friend design the centerpieces for her wedding reception at Sequoia in DC.  I'll be doing 16 tables in a space which will more or less look like this:

(photo borrowed from sequoiadc.com)

I'm thinking something simple and sophisticated, perhaps a grouping of vases with floating candles or tall glass vases filled with orchids.  But I'd love some advice!  Please leave any ideas in the comments section.

Bonnie Projects