That is fantastic! Thank you for taking the time to benchmark so carefully so that we know we’re making progress 
Your frame looks very very much like the design I just proposed at the bottom of this thread:
https://forums.maslowcnc.com/t/sun-with-face-new-stock-frame-design-sun-with-face
Any chance I could ask for more pictures of the way your motors are attached and any feedback on how you like that design?