I would use the oaks as street trees, keeping them in a line along the street and farther from the house. Nearer the house you could use flowering trees or some with special character attributes. I think you're creating a problem by having the walk be so close to the garage. The resulting bed is going to be pinched in that area. IMO it would be better if it's layout were simplified and of greater width at the approach to the courtyard (rather than flaring right at the end.)

gobruno, I linked the study instructions for Marion county below. This is the first I've seen for permit requirements. Rural Arkansas has almost no red tape for house construction. The study linked is a novel way of bringing science to the masses. The instructions lacked the detail a homeowner would need to complete the process. And for you, the table of multipliers won't work outside of Marion county. And unlike the study, your interest spans the summer months rather than the extremes of shadow location at the summer and winter solstice. The location of the sun and shadows is close to identical for a day that is x number of days before and after June the 21. For example June 10 will have the same sun as July 11. If you choose to do the study, I suggest you use June 1 and May 1. The May 1 date will give a good idea of the sun from April 15 to May 15 and also July 27 to Aug 26. The June 1 date will cover the May 15 to July 27 period. Do some winter dates too if you need to see if sun will reach house windows. Note that in the study, the location of the sun is given in degrees clockwise from north. North in this regard is geodetic north, rather than magnetic north, compass north, a state mapping north, or the north indicated on a survey. You will need to determine the orientation of the house relative to geodetic north. This can be done from stakes on the ground where the house will be built or from a site plan showing the house location if the geodetic bearings of the property boundary are known. My guess is that you won't find anybody locally to do your study. If you want it, it's a DIY project. And there is nothing you can't do, with guidance. Here is a link that might be useful: shadow study - Marion county style

As well, I would continue with the same pavers that you are already using. (I am a fan of the contrasting color edge. Maybe you will consider incorporating it into the patio and maybe later, into the walk.) As shown in the rendering, the wall color seems quite nice as compatible relief to the brick wall color of the house. I think they work very well together. However, I don't like the thin, dark cap on the wall, thinking it looks cheap (thin) and a bit schemey (dark, like it's trying to be an exact match to the brick, which seems like an unimportant goal to me.) A nice stone wall with a cap made of the same material (but thick ... 3 1/2" min.) would look a lot richer in the end. A cap which overhangs the wall face by an inch will create a substantial shadow, which will set it off from the wall. These shadows are generally underestimated in their importance and make a big difference in the finished appearance. For my taste, the gateway opening looks a bit tight, relative to overall size of house. I'd add a couple feet of width to it. It might help to keep in mind what is a main feature and what is a detail. Figure out main features first and details after. (For example, pick the wall color without knowing anything about its cap.)

Your initial drawing and photo did not give us any indication of architectural features of the house: doors, windows & other things that might need to be accessed. It would be important to know where these things are so that the planting scheme acknowledged and respected them. I thought that the 28' wall, marked "living room" was the only wall of the building and that the rest was fence, but I see from the pano that both 16' dimensions are also building walls and that they have windows and at least one door. It looks like there is a large opening at the right end of the living room wall and a little sidewalk, All these features should be indicated on the plan. Please add a north arrow to the plan, too. (I did not understand your description of directions.) Is there a gate along the fence that needs to be accessed? If so, it would need to be shown on the plan. You'll want the patio to abut the wall of the house marked living room. We don't yet know what doors are there and how they're arranged, but since there is at least one door at each end of this wall, it's likely you'll want pedestrian access for the entire length of the wall ( ...??) Then this pedestrian access (pavement) will project somehow out into the courtyard area. You'll want to expand the patio surface so that it is sufficiently large in order to accommodate the uses that you have in mind for it. On the other hand you'll want to limit the size of the patio in order to have room for the planting that surrounds it. While you can pinch planting space down to practically nothing in favor of maximizing living space, you must be aware of the fact that it's the planting space that has the potential to transform the patio area from dull and drab into something extraordinary. You should try to come up with a rough idea of square footage of space needed for the patio. For planting space I would suggest you have no less than 6' of bed depth (front to back) between the patio and walls/fence. Plants are not going to be happy in a 3' or 4' bed. It will be difficult for them show off in such pinched quarters.