Filtering is pain, especially in Analysis Workspace, where there aren't regex options. It would be great to be able to handle filtering at the segment level. I propose adding a new container option called 'filter' or similar.
This would do exactly what it says. Only show you data for items filtered within the segment. Because we have so many products and product categories on our site we are reliant on combinations of segments and dimension components to get the views we need. Having a segment that filters for you would save a lot of time and effort in building workspaces. We try to build templated workspaces where all that needs to be replaced is the segment. however, because we have to rely on the filter or a dimension value, we must take more steps to design the report.