I switched almost 2 years ago to macOS, I still have a hard time resizing windows and I miss how well it worked on Windows.
But as yourself I’m in love with my MB Air, I bought it as a placeholder while waiting for the new Pros but I can’t go back to a heavier machine to get performance that I don’t need out of it.
Sure it’s leaking in screen real estate and brightness, but I’m afraid there aren’t any alternatives to a fanless M1 Air.
I have been using the Magnet app[0] since 2013 for window management on Mac. You can use it to position/resize windows using mouse gestures (dragging to edges etc) and shortcuts. BetterTouchTool is another powerful tool that can be used for window management along with many other things.