First I want to say it a great work for developers who are involved in realtime-programming with rclcpp.
Accoring to the development model of ROS2, you should create a RFC in discource like this [REP-2014] RFC - Benchmarking performance in ROS 2 - General - ROS Discourse and create PR in ros-infrastructure/rep: ROS Enhancement Proposals (github.com) to demostrate your idea with a structural doc.
More info of how to contribute to ROS2 is in here Contributing — ROS 2 Documentation: Foxy documentation
Thanks.