Keep it simple...

Dinner parties can stress the budget.  I like to have simple arrangements for the table and that usually involves fresh flowers .  Rather than large bouquets which are tall and obstruct views, think about simple ways to use flowers or leaves in a repetition.

Hosta leaves are one of my favourites and I have lots to choose from in my garden.  I love the idea of massing different sizes and shapes of glasses/vases and submerging separate leaves in each one. 
The sunflower is a great choice for fall entertaining. If you don't have access to fresh sunflowers, there are realistic looking  artificial ones. The arrangement above works because of the meandering wave and colour variety.