Scheduling Between Departments, and filtering

We're a construction company who designs, fabs and installs custom structures.  I need the ability to plan our capacity in the future and would like to filter the Space Overview Gantt Chart by custom tags.  I understand how to do that but what appears it messy.  The filtered output is still showing all of the 'project' outlines (albeit collapsed) when all I really want is to see is literally the tasks tagged as Fabrication and Assembly.   Keep in mind this is across many projects so the cleaner the data, the easier to read.  There doesn't appear a way to filter everything else besides what meets the criteria.  So would it be better to build out separate spaces for each of those "departments" and also just include those items tagged with say, Fabrication, in the FABRICATION space?  In other words, all of my projects would be in my PROJECT space and any that I wanted tagged Fabrication or Assembly would also be included in those spaces?  I think that would work...is there a way to automatically add those tasks to a space by adding the tag?  hmmmm