The 'Show saved Filter' portlet is displaying a list of issues, up to a maximum value. Such maximum also determines the height of the portlet in the Jira page, as it is rendered with the page.
The following improvement would greatly improve the interest and performance of this portlet:
. The list of issues is asynchronously rendered in a DIV in the Jira page. The portlet rendering only inserts such DIV in the Jira page, with the necessary javascript that will get the issues list during the page rendering on the browser side.
. The height of the portlet is now a different setting from the maximum number of issues
. The limit to the number of issues displayed can then be greatly increased, as a vertical scrollbar in the DIV would allow quick scrolling in the list