I hear you about shade. Here's my experience with shade in my backyard that has southern exposure. My 2 20plus years old maples planted on the west side of my yard provide so much shade now that the grass is struggling to grow there now. In the corner under one maple we have small stones surrounding the trunk and not much sun nor rain can penetrate the canopy. Therefore not much can grow. If you put planters / urns be sure to know you will be going out there to water daily during the summer heat but you can get a "pop" of colour anywhere you like. By getting urns of varying height the final look is endless. Just check out sun requirements for the plantings.

Hostas are great perennial shade lovers, virtually indestructible, comes in a variety of greens and sizes ranging from citrus, variegated to blue tones with large jumbo leaves to wavy edged elongated leaves. If you can incorporate up lighting ...great nighttime look.

Good luck