In reply to Andrew.

Hi Andrew,
I agree with your assessment that you should make a many style specification within a template as you can. Leave the overrides to specific circumstances.
I would start by looking through these two papers.
A First Look at the ODS Destination for PowerPoint
A Second Look at the ODS Destination for PowerPoint
At the end of the second one you will see the whole PROC TEMPLATE step that generates the PowerPointLight style. You will see the PresentationTitle style element, which you can change to use whatever attributes you want. You can copy that and make the appropriate changes and create you own style from scratch or take the elements you need to modify the PowerPointLight style.

Jane