I had the same feeling about the 3-foot tall zinnias that I first planted, so last year, I went with the ones that were 12-18 inches. Worked out better for the area they were in. So you could try zinnias. I also like vincas and snapdragons, but haven't seen them reseed themselves yet. Marigolds are a familiar flower that does reseed. I put marigolds in front of my zinnias. This year, I'm adding dianthus. In my zone, they are fairly hardy, withstanding much of the average winter we have here, so they are still green even late into the winter. I haven't seen them reseed either but hope they will do that in this same area with the zinnias and marigolds.

Your house and patio look great. The raised beds complement them nicely in my opinion. Looks like the area is pretty open so I assume it gets a fair amount of sun? I was thinking maybe Nandina aka Heavenly Bamboo would work well in that space. That could qualify as zone stretching for you however. Anyway they get at least six feet tall (much more so in warmer climates of course). You might be looking for a more cold tolerant evergreen. Either way I hope this helps. Oh one more thought. I double checked the cold tolerance of Black Nigra Bamboo for you and it is considered to be tolerant to zero degrees. That could also be pretty risky with your zone but I think would look great in the 'block the view of the neighbors' bed. Kate

Nandina is frowned on in Austin because they are invassive and the birds love to carry the berries into the wild parklands. Clumping bamboo might do a number on your foundation. Lavender hates clay soil. Rosemary will need ammendment if the ground is clay but will not be as picky as lavendar. There are small agaves (A. parryi var truncata, A. Lophantha quadrifolia, X Manfreda Macho moca, Yucca glauca, Pale leafed yucca; Yucca pallida) that will go with the Red false yucca. Make sure you get the small one. Some of the hesperaloes that they have get large while others stay compact. The ground will need some drainage added to it. Some salvias will love that spot. Salvia gregii, Grey oak sage salvia macrophylla, also Mexican oregano (good in beans).Firecracker fern, Maximilian sunflower.

...perhaps it isn't popular in America, but here it's also used for driveways... mine is shingled, as opposed to bricks or paving... it's also great for digging into soil to improve the structure, I use the small 10mm for that... although I prefer lawn, it's impractical here for me, so it's been replaced with the larger type of shingle...as in photo... underneath is a weed suppressant membrane which allows water through...it never floods even after heavy rain... ...I also like the different coloured decorative stones, coloured slates and large pebbles, nearly all garden centres will have a range here... the choice can be bewildering at times... ....I just don't walk on it, bare foot...