You know, when they converted construction lumber from 1 5/8"X 3 5/8" to 1 1/2"X 3 1/2" for s4s (surface four sides) 2X4s, I had to relearn how to do layout. It wasn't that hard, except when we got mixed loads of lumber with both dimensions during the transition. But it made things simpler. Not better, simpler.
Of course, metric is simpler. So what? Think of using our "antiquated" English system as a mental challenge. Enjoy the challenge. Thinking is a dying art, with computers, calculators, and tivo. Your mind is like any other muscle. Use it or lose it.
We revel in our ability to come up with original designs, baits, and solutions to lure design problems, yet we whine about how complicated our system is. Rejoice in it. There's plenty of time to have it "simpler" when you're dead.
In the mean time, look for the challenge. When I die, I don't want to be in pristine condition, because everything was easier.
I want to slide into that last base like I was "rode hard, and put away wet"!
Unfortunately, I've already lost my mind, but there's hope for the rest of you. )