Another thing you could do to unify the porch with the rest of the house is change the curtains on the inside of the porch to match the curtains in the first-floor room on that side of the house.

Maybe paint the window *frames* on each part of the house so they match the other part of the house, or use a darker shade of the green on the porch and a darker shade of the beige on the rest.

I would also try for some dark green foliage and very pale green foliage in a few of the planted areas; right now everything is more or less medium green. I think some "silver mounds" could work well.

And there's the issue of *falling* that five feet because there's no fence. I would put a fence a foot or so back from each wall, and plant in the space between the wall and the fence to soften the line. On the second level, I would add benches -- some right up against the wall, and the others sticking out from the wall. Then add a table, fire pit, planter, whatever inside the L or U made by the benches.

I also like the idea of the landscaping allowance. Talk to the people who are interested, present them some options, and maybe they'll have an idea. Who knows, you might run into someone who would go for a raised garden bed along the edge of each terrace, or someone who thinks a series of koi ponds with waterfalls between terraces would be just the thing.