I've gotten into a couple of habits thanks to the KDE Mover-Sizer. The first is a quick one-two action where I first Alt-Left-click a window and throw it roughly into place (off the edge of the screen), and then do a single Alt-Right-click to snap it back into perfect view. I've already had a week-off with all the time this good habit has saved me.
The new version can also snap directly to the edge during regular Alt-Left-Click moving - so long as you are within the snap distance, it will lock against the edge of your desktop.
The second habit of one of resizing windows from the edge. First, I get them there, as in tip 1, then I grab a corner (anywhere in the quadrant is fine) with an Alt-Right-click, and drag-resize them while the two opposite edges (one of which is bang up against the edge of the desktop) stay put. This isn't so much a time saver, as a sanity saver. I'm very particular about the amount of white space that shows in folder windows, and it they don't look right, I couldn't leave them open. Leaving them open is what saves time.
Another thing I've started doing, is sliding windows up and down the edge of my desktop by Alt-Left-click+drag. The snap keeps them from moving left and right - it's like they are on rails! Very handy. And remember, it works on windows behind windows, too, and without bringing them to the front.