My proposed successor to a Moscow-Campaign-scale/-type game, Barbarossa's Climax: Moscow 1941, available as a free print (off, assemble,) and play game at www.CoatneyHistory.com/BarbClim.htm .
As relatively simple as it is, it is still a 4-player afternoon-and-evening - weekend - game. There *is* a system-introducing Battle for Tula subgame with it (like 1st Alamein is the subgame for my larger Battles for Alamein, and I have also just completed a smaller scaled Battle for Moscow game, Moscow vs. Barbarossa 1941 - at www.CoatneyHistory.com/MvB41.htm - which incorporates and demonstrates (in its smaller and more simple format) many of BC's basic design concepts).
6-day turns, 10mis/16kms per hex, brigade-division level, Blitzkrieg breakthrough phase (in addition to higher odds BReakthrough combat results enabling a unit to attack twice), Combat Odds Round Off (including UP) and *Expansion* Rule, Russian Katyusha Rocket Regiments (8, eventually), the obligatory Siberian Reserve Gamble, and more.
Over 300 units, most of them infantry having Entrenched/(Artillery-)Emplaced backside.