Right, applying a little digital sharpening will help a bit, your second picture for example is really sharp in the grass around the tree in the middle, but doesn't have a lot of micro contrast. That can be because of the lens, film, scanning, and notably lighting of the scene as well as the scene itself.
As has been mentioned, for more sharpness over a deep scene you might need to stop down further than f/8, but that depends on how large you want to display the image.
1 and 3 require a decision what you want in focus or stopping down more than would be good regarding diffraction I think. In 3, the plane of best sharpness might be behind the wall, where there isnt anything in the picture. Focus on the foreground wall or the horizon and live with the other being fuzzy?
I also struggle this in some with some scenes, especially foliage and grass (lots of fine detail) in scenes with "continous" depth rather than discrete planes, are problematic like that. Trying a different, less cluttered composition might be the best way at times (solution for picture 2?).
A while ago some article was discussed on this forum that essentially said that you need sharpness relative to the size of the objects/details in the scene, which tend to be larger in the foreground, and therefor one should focus to infinity rather than hyperfocal (which, as has been pointed out, brings only a certain degree of sharpness at the far distances). In other words, because the foreground subject tends to be large, we can live with less sharpness and still recognize it well.
There was a heated debate, and I think it really still depends on which details are important to you and what look you prefer. The take-away for me was that I consider focusing on the background if it has important fine detail and the foreground doesn't. Could work for your pictures.