Customization on Charts !! I would say go with how it works.
When you say 'Customization on Graph', does that means we will have to make changes in pcxml file?
Could you please provide further details on it, or what properties we will have to set?
I would say effort is more complex for this small requirement and waste of time to work on.
Has any one else faced same issue while working on OBIEE 10g, and applied any solution for it?