You might be able to launch different xpages or framesets from the database script using
notesuiworkspace.urlopen()
an example url launching an xpage: notes:///foo.nsf/xpage1.xsp?OpenXpage
also, if you do different framesets, one containing notes ui, and one containing xpages, you can create buttons or links to launch these framesets by user or by script.
hope it helps
Thomas