It would be nice to have an option to reduce bit depth for ortho generation. We are using 16-bit color for alignment, but don't need that color depth for orthoimagery. Image size is dramatically increased with 16-bit color and platform compatibility is also reduced. Also the internal metashape ortho files are huge compared to 8-bit and we aren't able to specify a minimum ortho resolution until the export stage so unnecessary HD space is used.
[edit] one way to do this (wouldn't address the issue of "build ortho" size but would enable 8-bit export) would be to add a colors_rgb_8bit parameter to the exportOrthophotos method, like has been added to exportModel and exportPoints in the API.