Which visualizations should I use in my dashboard or cockpits ?

With SSRS you can build very nice reports. You can make use of a lot of different report types like:

• Table
• Tablix
• Chart
• Gauge
• Map
• Data Bar
• Sparkline
• Indicator

Every report type has it's own purpose. To make your reports a success, the report should directly tell you what you need to know. One aspects of this, is to apply the dashboard design rules to your reports.
Another aspects is to choose the best report type. I will use a tree stucture you can use to select the best report type.  For your report you should answer yourself some questions about the report:

1. Comparison
1. Among Items
1. Two variables per Item: Variable width column chart
2. One variable per Item
1. Many categories: Table
2. Few categories
1. Many Items: Bar Chart
2. Few Items: Column Chart
2. Over Time
1. Many Periods
1. Cyclical data: Polar Chart
2. Non Cyclical data: Line Chart
2. Few Periods
1. Single or Few categories: Column Chart
2. Many categories: Line Chart
2. Relationship
1. Two variables: Scatter chart
2. Three variables: Bubble chart
3. Distribution
1. Single variable
1. Few Data Points: Column Histogram
2. Many Data Points: Line Histogram
2. Two variable: Scatter Chart
3. Three variable: 3D Area Chart
4. Composition
1. Changing over time
1. Few Periods
1. Only relative difference matters: Stacked 100% Column Chart
2. Relative and Absolute difference matters: Stacked Column Chart
2. Many Periods
1. Only relative Difference matters: Stacked 100% Line Chart
2. Relative and Absolute difference matters: Stacked Line Chart
2. Static
1. Single Share of Total: Pie Chart
2. Accumulation to total: Waterfall Chart
3. Components of Components: Stacked 100% Column Chart with Sub components.

A nice picture of this tree structure can be found on : http://extremepresentation.typepad.com/photos/uncategorized/choosing_a_good_chart.jpg

Click on the picture to enlarge.

Some observations:

• Pie Charts are ONLY used to show Simple Share of Total.
• Over Time Difference between few periods (Column charts)  and many periods (Line Charts).
• 3D is ONLY used to display distribution of 3 variables. 
• Few variables (Column Histogram) versus Many variables (Line Histogram)

Select the report type which is the best to show your data, therefor do NOT select a report type because it looks nice. If you want to have something which is nice, please buy a painting.

Enjoy using this tree structure, to select the best report type for you report.