Users new to us are not necessarily aware of the need to add/modify firewall rules in order to access their applications outside of the rack. The "VPC" name on the instance page (or Create Instance page) also does not suggest anything related to security for that matter. Here are two suggestions for users to have a better chance of getting the firewall rules right:

1. Create Instance: provide a link on/near the VPC name that lands on the Firewall Rules tab of the VPC selected by the user (perhaps open a new tab so that the user can stay on Create Instance); this allows them to confirm if the VPC selected is right for them.
2. Instance details: provide a similar link to the VPC Firewall Rules or add another subtab (named more generally as "Security", similar to other public cloud portals) that actually displays all the rules in that VPC.