A simple truth is that your yard could go from mediocre to almost spectacular based on one single change and that is to improve the maintenance of the grass such that it is uniformly green and weed free. If it's a grass that goes blond when dormant, then it should be free of green weeds in the winter.

You'll have to forgive my corner-cutting in drawing. I drew a single tree and cut and pasted it everywhere. I'm not suggesting that you should use that tree form everywhere. Just trying to save drawing time. The point I'm making for the overall yard is that the house looks overly exposed -- like a raisin in the sun. It needs the framing and sheltered look that some trees would give. Probably in the foreground of the lawn, single trunk trees, with canopies ultimately raised quite high, would look good ... with smaller multi-trunk trees being closer to the house.

Currently your house is smothered all around with shrub balls at its base. Instead of all the smothering, only four shrubs that correspond to four porch columns would be enough. I'm flanking the steps with "color," which could be annual or perennial depending on the details of your needs. Between the shrubs and "color" is a low groundcover that fills in the gaps. At each end of the house the bed is filled with perennials of a height that works with the house and the grade. The ends do not need to match each other. (Daylilies and Siberian iris come to mind if either of those would suit your liking.)

In the second picture I'm suggesting that the walk experience would seem much friendlier if there wasn't shrubbery pinching edges of the walk. It would be better set back away from the walk. For the size of house and yard, the walk looks very skinny, which makes it less inviting. You could easily change this my mortaring an 8" brick band along each side, flush with the walk surface. This would add 16" width and an upgraded, decorative edge to the walk. (I'm not illustrating this.)

Thank you so much for your detailed reply. The grass usually doesn't look that bad. We had a mild winter and weeds appeared everywhere. We've already treated it. We used to have annual beds on either side of the walk in the curved sections, but it became too much work watering and weeding. May have to modify your suggestion in the area of the post light so it doesn't have to be relocated. I agree some trees are needed in the yard. Husband has been reluctant to have trees obscure the house. I think we just need to find the right variety. Again, thank you for your suggestions.

"Husband has been reluctant to have trees obscure the house. I think we just need to find the right variety." It is starting with the right variety, of course. One decides up front if it is to be a single or multi-trunk, and then decides on details of its character and picks a tree corresponding to those choices. But regardless of what trees one chooses, there is no need, at all, for trees to obscure the house. One removes the lower limbs as the tree grows and keeps the space open for activities (like lawn mowing) and for light to reach plants that grow below (grass or groundcover.)

"May have to modify your suggestion in the area of the post light so it doesn't have to be relocated." My suggestions are only a semi-vague scheme. You must work out the details in a measure plan view so that you actually know what you are doing before you do it. But I'm not in the least suggesting that you relocate the light post. Just work the details out to be compatible with it. There is no reason a light post cannot be near a tree ... like 4' away. There is no reason a light post cannot be in a bed of groundcover. Your picture only shows so much. I have no idea about things in the yard in that area that cannot be seen in the picture. But when you work it out in plan view, maybe a tree and groundcover are farther left and the light post is just in grass. I don't know. But I'm sure it can be worked. out.

Husband has been reluctant to have trees obscure the house.

There is "obscuring the house", and there is "framing" the house. You don't want the sort of tree that is dense all the way to the ground, but some shade on that front would make it more hospitable to you and landscaping.

Using local native perennials, ornamental grasses and ground covers would give you more interest with less work than annual flowers. Whatever grows there in the wild.