First, I have never used Tivoli so this is only based on my Commvault experience/knowledge. Capacity license with Commvault is based off of the size of the last full backup. They don't care about how many secondary or tertiary copies you have. As for file system and sql backups, Commvault has an agent for both that you can install on the servers that handles this. I also don't think they care about how many of each agent you deploy. I'm not sure if you have a virtual environment or not, but if so, those VMs can be backed up at the Hypervisor level with Commvault which eliminates the need for an installed agent on the guest OS.
Hope this helps!