Normally in all servers, the outbound connections from a server will be originating from the primary IP of the server. This is the case in a cPanel server as well. So if an IP is blacklisted, or blocked, some where we may need to change the primary IP address of the server. If we are changing the network range this is needed.
A DNS cluster is a set of DNS servers that share and synchronize DNS zone files. Having a nameserver cluster will help your domain to be online even if one of your DNS servers goes down.
This article will help you to assign dedicated IP for your subdomains and addon domains. You will need it when you install SSL for such domains. Initially, this cannot be done via WHM.
Setting up a reseller can be sometimes confusing. Just giving the cPanel account reseller privileges may not help completely to keep it anonymous. Let's see what needs to be done to keep it completely anonymous.