Sticking with native or standard crop ratios is the norm for me. For my 3:2 ratio images I generally stick with that ratio when I do need to crop. On occasion I will crop to 1:1 or 4:3 for portrait oriented photos. Since I try really hard to compose in camera my crops are basically to tighten up a shot or get rid of a distracting stray element that snuck in the picture on me, such as the end of a branch, a car coming into the shot, or something else to that effect.
Once in a while, and I mean once in a while, I get bored and do a free-form crop such as this photo of dew drops on some leaves. I took this shot last summer and never looked at it gain until this evening. I marveled at all of the tiny dew drops but the remainder of the photo was a blurry distraction. Since I had to stop the lens down to get a bit more depth of field the bokeh kind of fell apart. The higher contrast black and white conversion helped some by darkening the background but I still found it lacking.
As I looked at the limited depth of field and the narrow line of in-focus drops I began to wonder, hmm, if I cropped just around the line of in-focus drops that would eliminate the distractions. At first I did a 16:9 crop and that helped but I had to push it more and go all free-form. So I did and I was left with a photo of the line of drops but maybe an even more distracting narrow window of an image. Certainly not standard. 😉
Maybe it would be a good banner photo for the blog!