Would it be possible to allow sub-grouping of projects in the Projects tab including sub-grouping by a custom field)?  Also a default sorting?

Our company has multiple branches which are set as a Group.  Each branch has multiple crew which I have created a custom field to select within the project.  Currently, I can only group by Group (branch).  I would like the ability to sub-group by crew under each branch.  I would also like to have the ability to sort by start date within each sub-group.  Additionally, the ability to save this view as default, would be helpful.