Upload & Sell: On
+1 @ the wider fov helps with the school/classroom setting vibe vs. a portrait.
@ the white powder ... backstory @ significance?
As to "centering" the image too often. I find myself doing that when I'm in a "fast paced" or anxious/excited state of mind. Once I realize I'm in "that" mode and am defaulting to center on "auto-pilot", I do one of two things.
A) I ask myself, are these croppable such that I'll be able to de-center in post. If so, no sweat, center away @ "get the shot" @ safety shot.
B) If they don't lend themselves for pp latitude @ crop to decenter. I'll consider changing my AF point to one of the non-centered points. I usually choose the nearest one (or two combined) to center that is above/right of center which allows me to be off-center @ both landscape/portrait orientation.
Then ... I resume "auto-pilot" mode at capture the moment, get the shot, safety shot, etc.