RE: Attacking as the Soviets in 42
The Soviets need to build up experience and morale. Fighting and losing helps experience, especially if losses are fairly balanced (Soviets will always be a bit worse at this point). Morale is from winning, and leads to Guards units when a unit wins enough battles.
A lot of times, I would attack but not move into the hex the Axis retreated from, as I believe a lost battle negates at least a portion of the benefit of a win toward achieving Guards status. And it will leave the hex with a lower entrenchment if the Axis moves back in.
No magic solution, it takes time and attrition at this point, with a good mix of units for the Soviets, and maybe even try rotating attacking units for each turn - you should be dropping the entrenchment levels with most attacks so stay focused, think Zhukov, wear them down, and be patient.