Sometimes you have too many visualizations for the size constraints of your dashboard. It can be tempting to throw every sheet onto the dashboard and just "make it work", but there are ways that you can keep those beautiful large views and utilize actions to hide your sheets and guide your users through your viz.
The first way to maximize a small dashboard (or focus the effect of a large dashboard) is hiding a sheet and exposing it on action. To do this, first check "Use as Filter" in the view that you would like to be visible initially. Then, add a layout container and place both views inside it. The last step is to open up the action you created (Dashboard->Actions->Filter 1), and change the "Clearing the Selection" preference to "Show All Values". Now, when you click the first view, the second one will filter, but it will disappear on deselect. You just doubled the effective space of your dashboard!
The second way to maximize your dashboard space sounds obvious: create more than one. If you do create a second dashboard, however, it's often hard to rely on the people who are going to be viewing your workbook to click on it. In other words, they may not even know the second dashboard exists. To get around this problem you can use a dashboard action. Simply go to Dashboard->Filters and then add a new filtering action. Under "Target Sheets" select the second dashboard. You will also want to change the filter to run on Select. After you've done that, all you have to do is tell your users to click on the source sheet and they will automatically be taken to the second dashboard, filtered to their selection.
What are your dashboard maximization tricks?