Another common theme of mine is "time". I'm certainly not alone in this. I often find myself daydreaming of time, watching the time, staring out the window at nothing in particular except for the passage of time. I spent far too much time staring out the window in the schools of my youth.
I was the first kid in kindergarten with glasses, so I was regularly told to sit in the front row of the class by well-meaning grade school teachers. If I had the sarcasm that comes with age I would have replied "but I got these glasses so I can see from the back" but it wasn't to be. As soon as I was allowed to pick my own seat, I relocated to the back. I often stared out the window even if I wasn't next to the window.
One thing I know about staring out the window is this; it's never as good as it looks from inside. I don't think it's a "grass is always greener" sort of thing. It just looks better from the inside then it really is. I find the same thing applies when I'm on the outside looking in, although that could also be said in a different context.