Looks more along the lines of a repair bay rather than a factory. Would an assembly line style picture be another idea? Multiple mecha on the line, each in a steady increase of assembly, with parts being delivered to the appropriate location.
Similar to pictures from the Willow Run facility, or a modern car factory.
Nice scout mecha, looks like either a large sensor or a covered missile launcher on the side there.
Very nice drawing. Question: how many does it take to crew your machine? From the size of the humans at the feet compared to the sized of the canopy it looks like it could about 4 people. Or is that a covering for a sensor array? Not criticizing, just asking.
I like the realistic lighting and the movieset atmosphere. I'm not really sold on the design itself. It looks like the Cockpit of a UH-1 Huey on top of two chicken legs. I would love to see something more daring than that.