Unless I’m misunderstanding the scale of the picture there doesn’t appear to be space there even for the Hydrangeas, let alone any more shrubs. The Limelights will be up over the windows in no time.

If the beds were about 20 feet wide you might fit all those things in. 😉

As floral said, Limelight hydrangeas are big plants that reach 8’-10’ tall and wide. They regrow fast enough after pruning that trying to control size isn’t possible without pruning several times a season and that would remove the flowers. Your windows will be half covered by your Limelights, and they look to be planted too close together.

I doubt that azaleas would appreciate being covered by the large Limelight leaves and flowers. They would be prone to foliage disease due to dampness and poor air circulation. And they would have to be huge to grow tall enough to be seen behind the Limelights.

Boxwoods have a couple of insects and diseases that can be disfiguring or fatal in some areas, so check that you have types that are healthy in your area.

No room. What you already have will smother the house.

Agree with the comments, just wants to add, your house is beautiful! Don’t cover too much of it up!

The simple answer is azaleas planted behind a Limelight hydrangea will be dwarfed by that plant and will not be seen.

In addition to various preceding remarks closer views needed for responders to make useful comments about specific details of your plantings going forward.