Deepen the beds. Get rid of any unhappy plant. But mostly, get control of the shrub sizes because they are on the verge of eating the house. If you trim them only once per year, hard, they'll look fairly natural throughout the majority of the year. The large shrub at the left, you either need to control and shape with hard pruning, or give up and grow it into a tree form. (The same is going to be true for the large tree/plant at the far right of the picture.) If you don't start trimming the juniper a lot harder, it's going to be lost, i.e., expanding in size to the point where it engulfs the surrounding property and you must remove it.

Main design issue I see is the rhododendron isn't big enough to balance the other, much bigger shrub at the left corner. (If the pointed conifer were near the right corner of the house it would do that but it is unfortunately just too far away to have that effect). And it's not possible now to catch up to the shrub to the left with a replacement planting where the rhododendron is malingering. So I would take the shrub to the left down (start it over) or out entirely.

And I certainly wouldn't add a second, big green blob to that left side - as appears to be happening in the above representation - and throw the planting in front of the house even more out of balance than it is already.

Thank you both for your suggestions. It is SO helpful to have a fresh set of eyes and an honest opinion. I will definitely get to work this week taming the overgrown ilex “blob” and the rangy, crazy juniper! There’s actually a nice weeping spruce behind the holly but you can barely see it.

Read again, Embo. it is an either/or, not "adding a second...."