Make a centerpiece for a long table?
For what occasion? Can always use mirrors down centers and candles with other elements to match occasion.
See if you can grab some ideas from here:
Get a couple of mirrored trays or just mirrors. Get. Candle holders and some pine branches spray paint the branches white pit pieces on mirrors then light candles maybe a Christmas ball or two also
Do you have a theme? I would add a runner to the table and then going with a tall centerpiece to draw the eye up, rather than across.