Hello @hsgwa,
that is a really cool analysis you provided us here! Great insight and easily understandable 
Just wanted to make sure that ePrisima is made aware of this. So I just add @Jaime_Martin_Losa here to have a look at it, if he not already did so. They are quite open to look for improvements At least what I can see is happening with Micro-ROS.
I’m not sure whom to add for CycloneDDS, if they are interested..?
@hsgwa, have you also considered doing your tests with other DDS implementations? There exists quite a few of them: ROS 2 middleware interface
Also, it would be worth pointing out which exact version from the different rmw’s have been used in your tests.
Maybe, FastRTPS would already be faster with their new shared-memory communication in their latest release (coming to Foxy): ROS2 Default Behavior (Wifi) - #31 by Jaime_Martin_Losa - ROS General - Open Robotics Discourse
Personally I would also be interested how GitHub - ros2/rmw_iceoryx: rmw implementation for iceoryx (shared-memory only communication) would perform in your tests
Also, I’m not sure if you are completely new to this community? Maybe you should check out the Real-Time Working Group: ROS 2 Real-time Working Group Online Meeting 16 - Apr 29, 2020 - Meeting Minutes - ROS General - Open Robotics Discourse @Dejan_Pangercic
They can probably help you out how you can continue to contribute to ROS2