As well as the factors you mention, remember that LH and LX are the only two carriers offering a top rated F service between LAX and Europe. Even if we add AF there are far, far fewer good F seats available each day between LAX and Europe than there are between Europe and TYO (to stay with your example). Given that AF and LX don't open up F award space to most of us, LH is in very high demand and anything they do make available is likely to go quickly.
Very good point
IMH. Following this logic it would even make sense to invert the award chart, ie 170K miles for Asia and 210K for the West Coast. But M&M being what it is, we'll probably end up with 210K for both directions rather sooner than later anyway.