As a mechanical engineer I use both the metric and the standard system. I do find the artificial simplicity of the metric system to be a false improvement. The removal the the ratio or fraction from a measurement system is a shortcoming in my eyes, not an improvement. Within the standard system you have "tenths" units if you wish. Anyone using CAD understands this. . I do find that the metric system is overly coarse when in the workshop, working with wood. "1/25th" of an inch is course when measuring real world objects. The ability to grab a scale that fits my needs is a plus. I can choose from 1/16th, 32nd, or 64th or 100th in a ruler for example. I can even decide to go "simple coarse" and go metric. I like to have choice. I do not find the metric system's difficulty in dealing with geometry a plus. I would say if you are looking for simplicity choose one system, or at least stick to one system on any given project. Mixing them together is unwise. Luckily ratio was available to those building the great cathedrals or the Parthenon, not sure how the world would look if an arbitrary unit of measure with the limiting factors of 10 was all that was available to them. The best example of this is the golden ratio.