Apart from the tasks smart tag panels, SplitContainer also provides C1SplitterPanel Collection Editor that can help you set a number of properties related to panels. It can be accessed by clicking on the ellipsis button (...) next to the Panels property in the Properties window.

The C1SplitterPanel Collection Editor window appears as the following:

In the C1SplitterPanel Collection Editor window, the right pane displays properties like BackColor, Font, Text, etc for each panel. The left pane displays a list of splitter panels along with Add and Remove buttons which can be used to add and remove panels, respectively.