Shrubs

Well, hollies are one of my favorites. They are evergreen, have lovely berries in the winter, are just about pest free, need very little trimming to keep them in shape. They come in shade lovers and sun lovers depending on the variety. They can be dwarf, upright, weeping and low, medium, or large again depending on the variety. I think they are worth checking out the best in your area. I plan to plant a lot of them as my budget allows.

I have seen the sand cherry in the stores and think it is very attractive. I do not know anything about it, other than I love the color.

Mahonia and juniper grow in your area. Junipers can get bag worms in Texas, I do not know about Missouri. Mahonia like shade or early morning sun and grow 3 to 7 feet tall. They have yellow flowers in the spring followed by blue-purple fruit in the fall and winter that is attactive to birds. I have never grown them, but have seen them around.

Spiraea is another large group of shrubs which I have grown. They are deciduous which is the only drawback. They have beautiful pink or white flowers in the spring and summer that cover the bush and make a nice accent plant in a bed. The size depends on the variety that you plant.
I saw a picture of the spiraea called "bridal wreath" with red tulips in front that was breath taking. Bridal wreath obviously has white flowers on arching branches. I grew one for years and not a single pest to be seen on it. Shirobana is a low mounding form with pink flowers and again I had several until last year when the prolonged drought and scorching hot air killed them.
We are in the southern most range of the zone for spiraeas and they are more suited for your region.