I would like there to be more dimensions control/options as well as I don’t use layout. I am using auto magic dimensions plugin which speed up my workflow and the developer of that plugin says there is a bug in sketchup that does not let one to allow dimension to attach to geometry and that sketchup where looking to fix it in the next API ruby update. Something like that anyway. I think that if you use mm for text size instead of points you should be able to achieve what you are after.