On a few watches Omega did that, its so that at a glance, the time only portions of the dial are all white hands (sub seconds, hours and minutes) while the chronograph hands are all blue (chrono seconds, chrono minutes, chrono hours). Just makes it slightly more readable.

 

The case should have the sunburst grain, as should the case back. Otherwise it looks decent. The cal 861 is a strong movement.

It depends if you really want a cal 321 and the money you want to spend. The cal 861 will always be cheaper than the earlier cal 321 watch.

 

Yes, and still does this, as illustrated by the very recent FOIS Speedmaster.

 

Good point!