I can't really give you any advice on the Inkberry. I don't have it myself, have seen it do great in some places. You might want to dig around the base to see if there was a planting issue (was it planted too low, is it too close to the house and the overhang is not allowing it to get the rain?). The Blue Boy should be fine for the Blue Princess as they are both types of Ilex x meserveae. If you don't see evidence of pollination after the first full year in place, you can add a Blue Prince somewhere to the property then, but I don't think you'll need it.

Pteroceltis: Looks like you'll have plenty to look forward to for generations to come. I only have one general comment on something from your list above. "Quercus prinus and Quercus michauxii (Chestnut and Swamp Chestnut Oaks): Will flank part of an alley that runs along side a pumpkin patch. Will be interesting to have a side-by-side comparison of these uncommon (around here at least) very similar Oaks." Actually (other than leaf morphology) these are quite dissimilar trees. Quercus prinus, the Chestnut Oak, occurs naturally around here on xeric upland sites in association with Blackjack Oak, Scarlet Oak, and White Oak, has huge flattened ridged and furrowed bark more like a Red Oak group tree than like the White Oak group it is a member of. It has big long oblong acorns, with a relatively shallow cap. I have never seen much more than yellow to yellow-brown fall color on this species, though it is supposed to be able to produce some orange. Quercus michauxii, the Swamp Chestnut Oak, on the other hand occurs naturally here in bottomlands, swamps, and along sedentary streams in association with Sweetgum, Blackgum, Overcup Oak, and Pin Oak, and has the typical scaly flaking bark like White Oak and Swamp White Oak. The acorns are also large, but not as long relative to width, and the cap covers more of the seed. This tree often has nice red fall color, though not quite up there in fluorescence with Nyssa or Acer rubrum. None of this will matter when under the care of a patient plantsman. It may matter in siting them, if you are looking for longevity and for natural reproduction of the species. Have fun with your menagerie, and report often.

Wow, that's a lot of plants! I don't have a list of what I'm growing in my little gardens -- sometimes it takes me a couple of weeks in the spring to realize that that weird looking weed in the corner is something I've had for years. I just assume that more plants than not will grow in this area! One of the more unusual plants I grow is agapanthus. Not a particularly hardy variety, this was simply a florists' plant my mother gave me four years ago. But it's come up reliably every year for the past three seasons in Central Ohio. It's planted against a south-facing brick wall with excellent drainage, and apparently doesn't realize it's not in zone 8+ anymore! One of my mother's more spectacular plants is a 15 year old calamondin orange that arrived as a little "get-well" houseplant. It spends the winter on the unheated glassed in back porch in Cincinnati, and now stands over 6' tall in the pot, and is nearly 4' around. It always has flowers and fruit on it, and we've picked 200 ripe fruits at one time.

I'd love to see a photo or 3 since with all those other plants I have a hard time visualizing what will go well there, and things like window height, the change in grade, and whether this bed will be at the top of the wall or farther back will make a difference to what looks good there. (I was envisioning one of those pocket gardens in front of a town house that one looks down on . . .) Take one or two photos from across the street, one or two from the sidewalk in front of your property so we can see the entire front yard and garden, and one from where folks will most often be viewing this particular garden such as the front walk or the drive. I can make Rhododendron and Carex recommendations, but my plant palette is much more limited by being 2 zones colder than you and at the northern edge of evergreen Rhododendrons' range. What height are you envisioning for the Rhodies? You could probably find a bunch that work in your zone by looking at the Rhododendron Society's plant finder which allows you to put in multiple parameters for suggestions and/or by visiting a few good nurseries. I grow several Carexes, including 'Evergold' recommended by Kirstin and 'Ice Dance', a vigorous spreader, and like them both, but there are some gold ones like 'Banana Boat' that look interesting as well. One plant IME that looks good from a distance in a mass the entire growing season is Hydrangea paniculata, which has varieties that range in height from 3 or 4 feet to 8 feet tall. They all go through a flowering sequence of chartreuse to white to pink, though how long they stay in any of the phases varies. Take a look at these blog entries on Hydrangeas by Detroit area landscape designer Deborah Silver to get an idea of how effective they can be when used with evergreens. If you found Kalmias boring, you won't want the Ilex glabra which has to my eye less appealing foliage and no visible flowers with black berries that are virtually invisible. However, keep in mind that your designer isn't looking at the evergreens as stand-alone plants, so the fact that they are just green most of the season shouldn't be a problem. They provide green in the winter, and some like the Kalmia will give you relatively early flowers, but then are just background while the perennials are flowering. Most plants aren't truly 4 season plants, so that is why a mix of plants (evergreen and deciduous, flowering, nice bark) is beneficial in good design.