from latest UG of ZD 9.6 - 35 is the max limit:
"In Walled Garden, enter network destinations (URL or IP address) that users can access without going through authentication. A Walled Garden is a limited environment to which an unauthenticated user is given access for the purpose of setting up an account. After the account is established, the user is allowed out of the Walled Garden. URLs will be resolved to an IP address (up to 35). User
s will not be able to click through to other URLs that may be presented on a page if that page is hosted on a server with a different IP address. Avoid using common URLs that are translated into many IP addresses (such as www.yahoo.com
), as users may be redirected to reauthenticate when they navigate through the page"
Since you are looking for something which needs improvement, i would request to contact your region's Ruckus wireless system engineer so that they can take up this as a feature request to the right team in the Ruckus.