As evidenced through some of my prior posts I also support the addition of new countries. In many mainstream World War II games we see a number of Allied countries, but only one Axis country. The addition of new countries would not only add to the gameplay, but make it unique unto itself amongst First-Person World War II games.
I think scenarios regarding the 1st Hungarian Armored Field Division, the Italian Alpine Corps or the Romanian's Lascar group, notably the 6th Infantry Division's defense of the German airfield at Oblivkavia, could be feasible in presenting a more favorable light towards these countries and against many of the condemning accounts which distort the history and overlook the disadvantages of Germany's Axis allies.
All in all, 1.725 million Axis Allied soldiers were killed, missing or ended up as POWs on the Eastern Front, a recognition of them in the upcoming game would be a nice tribute.
If any particular research or resources are needed, you can contact me.