Considering the goal of this document, I think more details on Item 11&12 should be provided by user case authors from 
the following aspects:

- Data management
- Workflow
- Job scheduling
- Resource allocation
- Security

Also, two more concerns (could be merged to one) might be helpful:

- How to deal with the diversity of all kinds of the Grid services provided by an existing Grid environment?
- What difficulites on how to leverage the services provided by an existing Grid environment?