I'm overawed by the level of scholarship going on here. You guys are researchers of the highest calibre (excuse the pun!). My take on the artillery issue is not so much the inclusion of higher-powered guns in the DF role (which I'm sure was exceptional), but rather the way that scenario designers tend to skimp on Soviet artillery. With a few exceptions ("The Bitter End" comes immediately to mind), the USSR is stuck with inadequate arty resources in almost every scenario, leaving the Soviet grunts almost unsupported. I would like to appeal to all scenario designers to take heed of the historical literature and pack the Soviet ranks with spotters of every kind, even at the cost of infantry, particularly late war. This implies a more detailed approach to the scenario briefing, and/or the beautiful and elegant hint I picked up from The Mad Russian in TPG, which is to place the enemy trenches and wires as "friendly" trenches and wires, so that they are seen in the setup screen. This simulates the kind of detailed knowledge of enemy lines (though not troop positions) which you would get from detailed recon.
To sum up: more Soviet artillery, fewer grunts, try the enemy trenches and wires as "friendly placements", to allow a certain amount of transparency.