Proportional painter
The current meta around the painter has you make the biggest cube possible before painting them blue or yellow, and then distributing these cubes throughout your factory.
While this is one neat solution, I feel that it's quite unfortunate that builds where colored sections could be made on-site (for instance, by coloring the output of a stamper before gluing the shapes back together) are left out as they would be massively inefficient.
My proposal is thus to have the painter use a proportional amount of paint based on the number of cubes in the input shape. This would now make both strategies viable: either you color the shapes in one place and cut those to size, or you bring the dye to the factory and color them on site. Having the painter on-site would also spice up the factory layout :)