IMHO nothing compares to peony in the vase, even roses. Fragrance, size, colors.
It is true that peonies are rather boring most of the summer, but you can inter plant them with nice summer and fall blooming perennials - just choose the varieties which are higher than peony foliage. I would love to grow roses a lot, but constantly limiting myself because their finicky character - they need pampering all time - bugs and caterpillars love them, they need fertilizer frequently, fungicide spraying, they need watering and winter protection. I do not not use Round-Up in my garden.
All I have to do for peonies - cut the foliage in the fall and stake some (but not all !!!) if they are face-in-the-mud varieties ( and I avoid them mostly ). Sit down and enjoy.
Deadheading and all work in garden is nice, but sometimes I feel that I do not need to spend a few hours a day in the garden. And when I go out for a week or month I do not worry about my peonies.
Back to your question - you can cut a little bit of foliage (15-20%) if it bothers you. You can do it when you cut flowers for the vase - after 3rd year in the ground. And you are perfectly within your rights to get rid of foliage once it starts to look ugly - dry, yellow or molded closer to the fall.
