Beautiful home, you should have a couple of landscape designers come up with plans for you, it will be well worth it. Decide which design you like best and reflect you then complete over time if there will be budget constraints.

I'd add a narrow vertical conifer or tree, such as arborvitae, upright juniper, to the sides to hide the drain pipe and build on the symmetry of the building. I'd suggest to add some more interesting plant colors and shapes, to add brightness and contrast. Im not sure what climate zone you live in, but variegated euonymus, or barberry might be possibilities. Its hard to see in this photo, but it appears the bed line is just straight parallel to the house. Adding more depth and interest with layers of heights and textures will help. It appears to be a more traditional architecture, so hedging with layers may be appropriate. Best! Joanna