Thank you for the feedback.
I do plan to limit what you can build at the start (maybe 10 parts), then add some sort of pickup that would add to your part allowance.
The AI is actually pretty cool in this game because it is built into the construction of the enemy mechs. Active parts like the engine, rotor and gun have two or three special AI switch settings. Active-when-on-target and active-when-not-on-target (clockwise and counter-clockwise rotation for the rotor). These parts all have a ray-cast (sensor) and a range to detect the player So there is one enemy that tries to orbit the player by having an engine on the side that pushes away from the player when it gets too close. It is a bit subtle but I could improve it in future enemies. It might also be cool to let the player construct enemies or even set up their own mech to be fully AI.
The screen size issues may be because this is the first game I have tried to run in the Itch.io webpage. I could not get the automatic dimensions and scale to work and just manually set them. I developed the game at 1920x1080 but it did not work correctly in the browser till i shrunk it way down. I definitely have to figure that out.
All good ideas for future development.