For reports that contain many filters, it would be nice to have the ability to search the list of available filters. Top level filter searching would search all filters (This Page, All Pages, this Visual).
Then at each level (This Page, All Pages, This Visual) there will be an ability to search those filters.
Default functionality would be down arrow / collapsed for all. When user clicks the down arrow, it turns into an up arrow, and reveals the listing of all filters in a fixed height scrollable window, with search panel, check boxes, and eraser to clear search.