I love your place!! It has so many possibilities!! You mentioned that things look better when viewed from one side only. I would suggest forcing the perspective. Design your walkway, patio, etc. so that it runs along the good "one side". Unless the shape of the walkway is ridiculous, people usually prefer to walk on established pathway. Another idea is to use the focal point. If you want people to look "here" but not "there", use plants with brightly colored foliage or interesting form "here". Use plants that catch my attention. In the "there" spot, plant boring things. You mention that June is the big month for your garden. For other months, add bright color artifically with a brightly painted trellis or other small wood structure. For example, in my front yard, I want people to look at my door and porch. I don't want people to look at the 4' tall utility box in the corner by the road. So, I introduced contrasting color, form, and texture by the door. The utility box is surrounded by boring indian hawthorne shrubs. (I thought about not planting anything there, but the utter lack of landscaping actually attracted attention.) I hope this makes sense and helps!

You are getting there :-)) You will have an entirely different perspective once you get the black pots elevated. And you can always add more color with flowering plants. What happened to the white/cream colored containers? You could mix them in with the black ones to make more of a statement. The pots in the middle photo (mostly blue tones) are still too lined up. btw, the groupings do not need to be equal in impact or quantity :-)

Before you start to spend money, even on a plan, think about how you want to use your space and what works or doesn't work now. A two-level living area (deck above, patio below) might not be your best bet because you lose the flexibility to move things around. Right now I see your outdoor "dining room" on the deck, your outdoor "kitchen" (grill) on the lower patio area, and I don't see a "living room" at all. Where would these outdoor rooms work best in your new plan? I agree with the poster above that is is highly unlikely that you will be able to build a 3 season room on the existing deck. Where are the doors to the outside from your house? Consider enlarging your existing deck instead of adding patio. I have a very large deck and love it. Instead of 2 small outdoor rooms I have one large one. I have lots of flexibility on where to place furniture depending on whether I am entertaining a crowd or just the family. As far as a cover for the patio, because I planted a tree just a few feet from the patio on the west side, I have shade there in the hot late afternoon, and a wonderful feeling of cool shelter. I put a small 10' x 10' metal gazebo on one corner for privacy from the neighbours' upstairs windows, and the gazebo cover keeps the dining table clean. You could do that now on your existing patio. As far as vegetables, consider grow bags that you fill with good soil and can place in the sunniest parts of your yard. https://www.bobvila.com/articles/grow-bags/

I put in an extension of a previous French drain to get rid of water running down the hilly backyard of my back to back neighbor. I situated the new drain pipe 90 degrees from the original one, all across my backyard margin. It certainly worked a great deal toward making the back yard less mushy when it rained. I just installed a slotted drain pipe on the edge of my patio, as water from the side yard would puddle and not drain on the patio. That's not quite done yet, but hopefully will work. The slotted drain is interfaced underground with the original French drain.