Shift/Rota flexibility

It would be very helpful if the shift/work patterns features were more flexible - or if we could add shifts more flexibly to particular teams of employees. At the moment, we are resource planning outside of the system and so there are some discrepancies as we are managing annual leave/sickness in the system. Would be great if there was some way to add shifts but not as 'set' working patterns that are rigid, and complex to change.