It will zoom to the entire extent of line/polygon features, but for points,
however, when zooming to a single selected point, the view zooms in a fixed percentage.
However, I noticed that each time you press the "zoom to" button, it zooms in to the "next" fixed percentage level.
I do not see anything about modifying this behavior.
I normally just click it once to center/zoom to, then I type 270 in the scale box and hit enter.
R_