Without knowing more about your goals for this area, my advice would be to keep the existing shrubs in place, as they appear to be healthy yews and are therefore excellent kept pruned into an evergreen background hedge.

I would consider moving the ubiquitous pyramidal evergreen somewhere else, and replacing it with something that has more personality.

I would layer a few sizes of flowering shrubs with the foliage and bloom colors that would enhance the character and colors of the annuals and bulbs that I would use to add a burst of color to the edges of the planting beds.

But that's just me, lol.

My husband hates the yews with a passion, and I'm not a huge fan either, so even though they are healthy, they are not really in our taste. Additionally, they are apparantly sheltering some carpenter ants or at least used to. We could trim them away from the porch, but we'd rather just get rid of them, but up a porch railing, and plant some more interesting shrubs and plants.

Right now we are looking at a combination of hydrangea, rhododendrons, azaleas, and maybe some holly. We'll build the area slightly up with some landscaping stones but not till the yews are all gone.

Azeleas and rhododendrons do not do very well in the Midwest. It gets too hot in the summer. Yes they will survive but not flourish. Ever seen them, in England for example or even China, that's a rhododendron/azalea
Think about the name hydrangea, it likes water, try for drought resistent plants. Try a variety of Midwest perenials, echinacea, black eyed susans, butterfy bushes.
All my experiences when gardening in the Midwest are on yardspace.org.. both good and bad. I have made very mistake in the book.