Kirk
I remember, that in Photoshop I had the same issue, when enlarging a picture to a certain degree. Could be a matter of resolution/monitor size/etc.
I prefer to have some grey background around the picture, when it is getting very close to the edge, as in non zoom mode, it somehow disturbs me. Also I find it to be too big, for I have to choose pics, which normally don't get printed double page all the time (unfortunately). So, to see the effect or appeal of a photo, I find it easier to choose, when it has a size close to the print format. My favorite would be little bigger than the zoom 1/4 without moiree.
Of course the german keyboard has a T, but it's in the middle of the keyboard and you can't rest your fingers on the other keys. So for me it would be more relaxing to have a key at the left edge of the keyboard like ^or A or S for example, or just be able to choose it myself.
Greetings
Ronald