I'm looking for suggestions for a replacement for my Dark Towers penstemon. In its current location it's not getting enough sun and seems more green than it should be. I'd like to move it into more sun and replace it with a plant that has all its qualities but will settle for part shade.

Tall enough to grow above the hosta in front, purple foliage, pinkish blooms, and something that disappears as much as possible in winter. I'd like to be able to cut it down like the hosta and lilies already in that bed.

I've looked at Negligee bugbane but don't care for the white blooms. Brett Marie something but don't care for the orangey flowers. Chocolate Joe Pye? I've seen a purple St Johns Wort....

Any suggestions? Thanks!