Tank Battle: 1945 adds to the base game . The big changes I noticed are new units (flamethrowers, airborne and engineers), unit stacking for some types (notably mortars) and road reinforcements that allow more units to arrive at once in the same hex. These are welcome improvements, but there are no new nations and the missions seem to work the same as in Blitzkrieg .
I didn't enjoy the sampling of missions I've played as much as the previous game. They tend to be much larger, which involves moving a lot of units. Missions also tend to be straightforward attacking or defending control points. As a result, they create more busywork and fewer impactful decisions. Still entertaining, but not as excellent as previous iterations.