If you want to play with somebody else, houserules will have to be short.
So here we go:
Gripe #0: "Spotting/PanzerBush/Smoke/Aircraft/Lack of Americans and Brits"
Rule: "Use the Panzer Leader Rules".
Gripe #1: "Heavy artillery is too powerful, small mortars are useless"
Rule: "For direct and indirect fire, (H) or M weapons with less than 10 Attack Points have their Attack Points doubled, while (H) or M weapons with more than than 15 Attack Points have their Attack Points halved."
Comment: A 3" mortar fires 200 lb of projectiles per minute, a 25pdr (Sexton) 125 lb per minute.
Gripe #2: "Combined fire against "A" units is unrealistic, if one SU-76 can't penetrate a King Tiger frontally, neither can two."
Rule: Fire against "A" targets cannot be combined unless the lines of fire go through different non-adjacent hex-sides on the target, viz "Outflanked":
Comment: Vehicles will eventually take disabling damage from massed small caliber fire and, but not a whole platoon in 6 minutes. Outflanking lets you shoot at the weak rear and side armor of your enemy.
Gripe #3: "Spotting is too difficult, Reconnaissance by Death is the only option."
Rule: "Instead of attacking or moving, on a die roll of 5 or 6 in its attack phase, a unit spots a single unit, infantry within 4 hexes, or non-infantry within 10 hexes.
Comment: If you have less than an hour to take the objective, Reconnaissance by Death isn't completely unrealistic, but there is also Reconnaissance by shooting, binocular, and sending 1 guy forward.
Gripe #4: "The poor training of Soviet Units is not represented."
Rule: "A player may re-roll any natural 6 against a Soviet target, once per attack".
Comment: The USSR lost 10 times as many men in combat as the UK and USA combined. In the game most of the Situations favor the Russians, so we can make things more difficult for them.
Gripe #5: "Nobody ever runs away."
Rule: "For every "D" result on an undispersed unit not in a Fort, roll a D6, a 5 or a 6 forces the unit to move a full move immediately, and the "D" is changed to a "DD".
Comment: Withdrawing is common, even among veteran units. The "DD" encourages you to move somewhere safe.
Gripe # 6: "Infantry in towns turn into tanks."
Rule: "The only Effect On Defense for Town hexes is that Vehicles get a +1 DRM, non-Vehicles get a + 3 DRM, individual units may be attacked."
Comment: If an SU-100 attacks infantry, they are better off in the open than in a town in PanzerBlitz.
Gripe # 7: "Nobody can start the game dug in."
Rule: "The Situation may permit the placement of immobile Improved Position counters at the start of the game which offer +2 to attacking DRMs."
Comment: A Soviet defender would usually have everything dug in.
Gripe # 8: "Where is the mud and snow?"
Rule: "Optionally, vehicles moving off road (or partly offroad) at more than half speed (round up) must roll a 1-4 after the end of their move, a 5 or 6 gives "D" result."
Comment: Tanks were constantly getting stuck and unstuck when moving offroad. Driving 10 hexes offroad in 6 minutes (25kph) is risky in ideal weather. Obviously the 1-4 might vary by time of year, or in marshland, where offroad travel might be impossible. In heavy mud and snow movement rates would drop to 1, but that would be boring.
Gripe # 9: "Where are the Squad Leaders, running around rallying the broken units?"
Rule: "A Soviet unit must roll a 1-4 on a D6 to recover from a "D" or "DD" result, unless adjacent to a undispersed friendly unit"
Comment: Invisible Squad Leaders actually are running around rallying your troops, you just can't see them. The Soviets have fewer Squad Leaders, and running from unit to unit takes time if the troops are far apart.
Gripe #10: "Where is Fog Of War?"
Rule: "Use counter stands rear towards enemy."
Comment: Just a paper triangle with a slot cut in it. Once the counter is spotted you may dispense with the stand,