I'm weary of looking at uninteresting planting in parking lots (and elsewhere) that do nothing for the natural world. Why not include a diversity of shrubs and trees? Why not include grasses and perennials? Why not include rain gardens that help filter runoff and provide mini-wetlands that might support a few dragonflies?
I've bumbled across a few good examples lately. The photos above, of parking lot for a Portland bakery/coffee house were nice.
And the urban parking near UNC Asheville and the Botanical Garden of Asheville, planted in natives, gets my kudos for providing a sense of place.