Margin spacing on graduate school applications (PhD) in the US
Whenever in doubt in such situations, it is always best to err on the side of fewer words. You do risk annoying the reader (who will see that your margins are smaller than the margins on the others they are reading), and you are assuming that the reader will actually finish reading your longer statement. Page limits are there to guard readers' time, and if they only have x minutes to devote to each statement, your longer statement will not be as thoroughly read and digested. Yes, they should probably have word limits to get around this margin problem (my Uni works with word limits, not page limits, for this reason), but you do risk diluting the time they spend thinking about you. 

While I know you think your three experiences are so significant that they each deserve extensive treatment, being concise about important things is part of academia. For example, I recently had less than a page to display how my research background is world-leading enough to warrant being awarded €1.5million. You are given 2 pages only to describe why you want to go to graduate school. Having to express important things in little space isn't going to go away as you progress with your academic career; as time passes, more info goes in less space.