It isn't possible to have only coco and graphic staff reviewing uploads. Reasons are simple:
1. players will have to wait even longer than they do now
2. they don't spend as much time online as GPs
3. in the end, all views will differ in one way or another on whether an upload should be approved or not

Upload bans aren't permanent.
As for some kind of indication of staff online, this has been brought up many times and why there won't be one due to spam and people using it to their advantage to break the rules when none are on