Basic reporting functionalities like scaling factors, number format should be available at report level as a standard like zero suppression
Users should be able to decide scaling factors on the fly if they wish to see numbers in absolute value or in thousands/millions. - I know for the first one we can create a business rule to convert numbers in thousands/millions and we are using it now, however it would be handy if it is available as a standard in PasteViews just like Zero Suppression.
Users should be able to select number format if they wish to see data in decimals and if yes, how many digit they would like to see after decimal point. - We can set format for dimension elements but that does not allow users to select how many digits they want to see after decimal.
Use ID and Description in the report - We can currently do this by selecting aliases for the same from edit view screen. However, it would be handy to have an option by default available to turn this on and off just like zero suppression
One important point to consider for point 1:
With a business rule in place, you can't use the column for input in a planning scenario. So it has to be the number format.