I don't think you can currently, looking at the config file that gets pushed down it just takes them in order so the first is your primary pool with the others as backups. If you want to change the order you need to remove them and add them again to get the new order in the UI, then the config change will get pushed to the miners.

I think the ZenController is a really cool idea, a lot of people will find it invaluable, it's just maybe not quite ready for prime time at the moment. That said, being an 'IT guy' myself I really don't want a managed offering though no matter how good, I like to tinker and that requires root access, hopefully I will still be able to get the firmware updates through another route.