I'd look at a groundcover. Cotoneaster dammeri would be hardy in your area, evergreen, flower nicely in spring and produce red berries in late fall. Low and spreading. A very simple planting like that would suit the rather classical archietctural style of your home.

Judging by the landscaper's list, I'd say he or she assessed this area as relatively hot and dry. Also, that slope is a major consideration in terms of the ability of the plants to hold on to the soil and survive erosion. I also think you will not be climbing out onto that hill for much maintenance. Given those thoughts, I think several of those choices make sense....the low juniper is actually a very good idea there, the nepata and the coreopsis as well. The barberry is actually a tough plant that would do well there, however, even the crimson pygmy is considered to be invasive plant and should be avoided. So, it's good you don't really like it. (Sadly, I'm fond of it, but can't use it in good conscience.) If you do use the Miss Kim, I'd put them at the top or the bottom of the slope....I'd feel nervous about their ability to hang onto the steep part of the slope. You might also consider a purple sand cherry. I also think the boxwood along the stairs are a nice idea for framing the area. For trailing over the top of the wall you could do some creeping phlox, and/or the wonderful Homestead Purple verbena. Just some thoughts.

Too much sun shouldn't kill a J. maple but it can cause leaf scorch until the tree gets used to it. Extra deep waterings can help to some extent but the tree will eventually become acclimated. Crimson Queen is considered to be quite sun tolerant, too. There is also a big difference between no direct sun and complete shade :-) Complete shade is usually created by wide overhangs or dense surrounding foliage. The north side of many structures receive minimal direct sunlight but are often very bright, indirect light situations. Many plants grow well in this light situation and your maple may be fine in this location. I have a red laceleaf maple (cultivar unknown - it was there when I moved in) that IS in complete shade from very large surrounding conifers. Not only is it thriving but its color is still very intense and deep red.

Great question. I understand completely. I'm very dissatisfied by the aroma-lessness of the newer cultivars. I just decided to go with the plain ole sempervirens, in spite of winter bronzing, box die-back disease, blah, blah, blah just to be sure of the smell. Its not really as slow a grower as folk would tout, but then, nothing is. I'd love to know the results of your nasal search. One thought is that you may wish to post your question on the Shrubs forum.