Honestly, it sounds like you may be trying too hard.
You've tweaked this and that and still don't seem to be happy with your images. To me, they look like they're composed fairly well and focus seems to be working for you; which is more than I can say for half of the pictures in my family photo album.
Try something and see how it works for you.
Do not go into the menus and change anything at all. Go out in your back yard and pick a flower to take a picture of. Turn the knob on the top of the camera to the flower/closeup SCENE mode and take a picture of the flower.
Then change the SCENE mode to landscape and take a picture of the entire back yard. Compose and focus the way you normally do; just don't try to adjust or edit anything in the camera or on the PC.
Post those two images and tell us what you see that you don't like. It may be that your PC is set with the brightness too high, or your the color may be set too warm or cold.
See how those two pictures turn out. See if they are closer to what you want than what you've been getting. Then let us see if we see the same problems you do.