It's a pretty simple suggestion that I think would really improve ship building. Maybe have a toggle-able box on the in the bottom left of the blueprint mode that shows a colored dot where the center of gravity is and moves when you place new modules.
This would be nice, and would help know how effective thrusters would be and how they'd rotate around the CoM.
https://trello.com/c/vlt9BB3s/37-option-in-build-mode-to-show-the-ships-center-of-mass
Center of Mass, Center of Thrust, Power Distribution, etc. All as checkboxes.
