I know I am a little late here but I just finished planting a new 8' wide by 22' long bed. I used phlox, both in a light pink and a darker Rose pink color. I planted both a raspberry pink group of Salvias and several smaller purple or blue purple Salvias. Everything in pinks and purples using groups of either 3 or 5! I just love the idea of that color combination! The Salvias are going full blast and the phlox are just starting to bud.
I am excited so far with the look of the bed. Plus as you guys might know, they all re-bloom if you dead head them.
I have two areas towards the back of the beds where I am going to put some tall, feathery Liatris or Gayfeather in there. It has a pink/purple flower and should offer a certain texture with its leaves and a little more height.