waqar,
your first issue is a common issue where user devices has not have intelligence and are NOT aggressive enough to change AP when there is a better one available. You can explore SMARTROAM feature which will address some of issue from Ruckus side. Btw - this is more of client driver issue.
Yes, its possible to do so however you need to create a new SSID and assign that to specific AP so that user can see, differentiate from others and connect to it