It would be beneficial to be able to conditionally show a design attribute in the template builder. For example:
<design:attribute name="attribute1" label="label here" description='Description here' datasource='Type 1,Type 2,Type 3'/>
<design:attribute name="attribute2" label="label here" description='Description here'/>
Given the tags listed above, the ability to only show 'attribute2' if, for example, 'Type 1' is selected in 'attribute1' would allow for greater end-user customization of custom components. Allowing developers to build more robust components which could reach a wider user-base.