The Blue stuff is probably bluestone, don't really know what you are useing as mulch though, would like to get more specifics on it.
Also I would have to know the cultivar and even species of dogwood before I could tell you whats smaller than it, some dogwoods are only 6 inches tall (Flowering dogwood, we have it in our rock garden) and others are 15-20 feet tall. As you may have picked up somewere I like to encourage people to produce food on there own, so I'm going to recomend Evans Cherry go be near it if you want sort of a small clump of bushes, they make an excilent pie cherry, a man by the name of Bali smuggled an evans cherry out of canada and patented it in the US so they may be under the name Bali, but they should not be, because it was out and out theft, a good polinator for this species is the purple sand leaf cherry, with brilliant purple leaves in the classic cherry leaf shape, these produce bird fruit wich will bring in lots of featherd friends to feed upon the bounty of your yard. I'm not familiar with what zone you live in, so I do not know what other types of bushes and trees you could grow, How cold does it get on your property in the winter, I need a number.
Sorry if I haven't been more helpful, it would be easier if I knew just what it was that you are after, thanks.