Roughly, punching a hole in a suitable point of the enemy front and driving through it with mobile mechanized forces that then spread out to cause general chaos and confusion in the enemy's rear areas (and hopefully capture strategically important point while they are at it). Less mobile forces follow through the gap to consolidate and if possible roll up the enemy lines from the flanks.

The Soviets were big on using raw weight of artillery fire to create the initial opening, I understand.

It was not really a matter of luxuries.
Given that early to the war the main Soviet concern was to throw about everything short of the kitchen sink at the Germans to stop or at least stall them, I'd say some rather odd things would have ranked as "luxuries" they didn't bother with. Soviet armour suffered from poorly and hastily trained crews (as well as in many cases severely overworked tank commanders due to the common two-man turret arrangements) and, I suspect, tended to have rather low life expectancy even in good tanks like the T-34. Wasting too many radios on what were essentially expendable stopgap forces, or the time required to teach the crews to operate the devices for that matter, was quite likely not a very high priority - ergo only commanders' tanks could be counted on to have the devices.

They were leaving fuel gauges out of aircraft too at the time after all...

It was of course different after the worst crisis was over and the Soviets had some breathing space, and could take a shot at being skilled and sophisticated instead of just desperate.

Incidentally, I've seen some photos of T-34s and other Soviet tanks with wire-mesh side panels rather resembling the German Schürtzen. Given the prevalence of shaped-charge antitank weaponry among late-war German infantry it would certainly seem sensible for them to copy the idea (especially as they had way better industrial capacity for manufacturing thethings en masse than the Germans if it came down to that), but does anyone know anything specific about this ?