The only place that team filters can be managed is through User Tasks. This isn't a very friendly way to manage them to say the least. I propose that a tab be added in Administration-> Teams when viewing a specific team called Filters. This tab would list all of the filters currently available for that specific team. It would give a better way to see all of the filters currently created, allow you add, edit, or delete filters as well. Looking at the bussiness_rules table in the database they are only tied to the team, so I believe this would be the best place to be able to manage them.