MancRy
Well if CX got MAN-SVO traffic rights - happy days but would the Russians allow that? - I somehow doubt it, unless you know otherwise.
Also I note that you make the very valid point about filling the back end of the a/c too. That's where it gets tough.
Moscow is hardly a short break destination - ultra expensive and unwelcoming to the visitor. Frankly not a great deal to see either once you've done Red Square and the Kremlin.
St. Petersburg though is radically different - a real touristic gem waiting to be discovered. Less C Class traffic though - can't seem to win.
Cheers
VHF