Well, I'm biased as I designed Kharkov '43 and Moscow '42, but I would strongly suggest you do look at Moscow '42.
It has so much content that it is really the equivalent of a couple of titles.
With both a full winter and summer campaign you get a decent feel for both types of warfare. There are 57 scenarios of various sizes where more normally the average Panzer Campaigns title has 30.
All in all though they are all great and once we get the Gold upgrades done for Western Europe/Mediterranean/North Africa, you will be even more spoiled for choice...!
All the players notes and maps are available for free so worthwhile having a look here ;
http://www.johntillersoftware.com/Panzer...cow42.html
David