Actually it is a tough ui for new users to quickly grasp as when ever i click on a text feild in the dropdown to change something it unchecks a check box in the dropdown. but it works so that is good enogh for me, it is a great use of space.
Also just a design thought, would be nice to have the information under Edit Report - Report Parameters stored with the paramter query as default values and have a per report override stored with the report. (I have over 10 reports with identical paramter query customizations/options).
I suppose the way to build that now would be to use a report as parameters, this would give me more customization options as well.... I haven't seen an input box by itself, but pageview could be used.