I just added two suggestion items to my feedback for SSAS2005.
The first suggestion is about the perspectives: it would be useful to select member filters and default members on each single perspective. Another important thing could be to be able to rename a dimension/attribute/measure into a perspectve (then you need to add perspective to translation system, so it would be good to translate only the changed descriptions).
The second suggestion is about drillthrough: today you can drillthrough only the real measures. It would be better to drillthrough also the calculated measures: to do that, it would be useful an MDX expression that defines a subcube (of “real” cells and not calculated ones) to be used for drillthrough in place of the original selection/cell.
If you agree, vote and give feedback to these suggestions!