Optimizing cPanel incremental backups for massive data changes

We're currently grappling with significant challenges regarding our cPanel backup strategy for several large client sites, particularly those experiencing very high daily data churn. Running daily full backups, while robust, has become increasingly unsustainable. The sheer volume of data changes means each full backup operation consumes an inordinate amount of server resources, leading to noticeable I/O contention during peak hours and extending the backup window far beyond an acceptable timeframe. This resource strain is not only impacting site performance but also making it difficult to maintain a consistent backup schedule without affecting our core services. We need a more efficient approach.

Our primary goal is to transition to an incremental backup system to mitigate these issues. What are the best practices for effectively implementing and, crucially, verifying cPanel incremental backups, especially when dealing with such massive daily data changes? We're looking for insights into specific tools, scripts, or configurations beyond the default cPanel options that can handle this scale. More importantly, how do you ensure the backup integrity of these incremental chains, and what strategies are recommended for rapid RTO (Recovery Time Objective) in the event of a catastrophic failure, given that restoring from a long incremental chain can be complex?