It depends on the objective of the war. Nation building is basically impossible. Killing the crap out of an enemy until they surrender is pretty effective historically. Killing the crap out of select targets while avoiding excessive civilian casualties is generally ineffective. WWII was a total war scenario, the US and USSR absolutely killed entire areas of German and Japanese towns.

but by taking and holding territory (and while awful being less awful than the Nazis.)

It wasn't just a matter of territory or PR. The soviets placed a huge emphasis on logistics, both their own and the enemy's. A typical soviet operation was to attack with a first wave to find a breach, then send a fresh second wave into the breach to cause as much damage as possible to the enemy support crew. At that point, the second wave would evaluate whether they could hold against enemy reinforcements, and if not, retreat before they even arrived, satisfied with the damage they caused.

The key difference in their approaches to war was that to the soviets, every worker who manufactures goods or drives a supply truck or fixes a tank was just as important to the war effort as the person on the front charging the front line. The Nazis placed all the emphasis on "warrior spirit" or whatever nonsense, the people on the front line were the only ones who mattered, and so to retreat from a position, especially without a fight, would be seen as cowardly (with potentially severe repercussions) even if it was the correct decision.

The differences are also apparent in military technology. German tanks were very powerful, in line with Nazi power fantasies, but they were expensive to build and difficult to maintain or repair. Soviet tanks were much cheaper and mass produced, allowing them to field more of them, and of course the AK-47 is famous for it's simplistic design, if something goes wrong, it can easily be repaired in the field. As the war went on, German tanks and aircraft became increasingly convoluted and overengineered, ignoring that the actual weakness was logistics.

USSR being less awful than the Nazis is uhh arguable, if you look at the Eastern Europe. They had more people to throw into the grinder, that much is true.