This was a quick fix for a matching pair of niches in a lovely formal dining room. I already had the bottles in my staging inventory. Usually I use one as a stand alone accent piece or perhaps a grouping of three for a large space. I don't usually fill them with anything.
I have a variety of ropes and tassels, which come in handy for door knobs, towels, or hanging on artwork.
The Asiatic Lilies were from a local grocery store and $10.00 a bunch. The twigs from my yard and soaked in glycerin. They will last for years. The arrangements stand 36" Tall.
Fresh floral arrangements are really special touches for an open house or home tour. I love all my silk plants, but nothing beats the real thing, if you can swing it.
Adding pre-open house prepping can give you extra income and creates another niche (couldn't resist that one - sorry).
Floral arrangement in the niche.
~close up with room background~ 
great arrangement! i think your recommendation about tassels is great!