After serving 20 years in the military and watching countless WW2 movies and being a devoted military board game player, there are some rules I just don't agree with. Needless to say, we have altered these rules and in some cases made up some of our own. Here are just a few of the rules that some of us don't agree with or tried to improve upon. Besides, TOI is just a game and if you don't like something than be creative.
MG and Flame Thrower: Our gaming group does not allow MGs and Flame Throwers to attack heavy armored vehicles such as tanks. Trucks and Half-Tracks are affected as they are light armored at best and any troops that may be with them.
Hedgehogs (Tank Traps): We do not allow any vehicles to pass through these hexes. They are there to prevent vehicles from passing and in some cases set up to cause a diversion into another well protected area. Sure engineers may atttempt to remove them, but we do not allow this either due to the shortage of time for the scenario. Imagine D - Day if the engineers attempted to remove the obstacles that prevented the landing crafts from getting closer to the shore. These obstacles are pretty big to say the least. We also allow cover 1 for direct fire against infantry if in a hedgehog hex.
Wire: We only allow vehicles that are tracked or fully tracked to enter a wire hex as well as any infantry. Engineers are able to use a special action to remove the wire and become fatigued in doing so. Tanks may move through a wire at the movement cost specified and the wire is removed upon exiting the hex (we assume it has been flattened or pushed out of the way). As mentioned earlier we do not permit trucks from entering a wire hex since they are wheeled. I suppose you could make up a rule of some kind dealing with bogging down and such but that is up to you. Infantry must stop on a wire hex for obvious reasons.
Woods: We negate the cover for indirect fire due to the damage caused by flying branches and such. Vehicles that enter a wood hex must stop. In our case we have a bogging down table we use for the vehicles when they enter certain terrain such as woods. Of course if a road goes through the woods then there is no problem.
Rough Terrain: We apply a cover of 1 for every rough terrain hex between the firer and the target if they are on the same level only. Since we don't know how rough the terrain is we simply allow fully tracked vehicles such as tanks the ability to enter but they must stop upon entering.
Entrenchments: We allow a cover of 2 but a cover of 4 against indirect fire.
Assaults: 2 squads (no heavy infantry weapons) may assualt a hex. We don't allow any support from other units as that would put your own troops at risk of friendly fire. Assaulting troops don't get any cover (we use an ambush rule to sometimes negate that). We even allow squads to assault tanks but if they are protected by infantry than the enemy infantry must be assaulted first by at least 1 squad. Trucks and Half-Tracks are part of the enemy infantry group and enemy tanks are seperate. When assaulting enemy squads and light vehicles the defender decides where to apply the damage. When assaulting tanks we use infantry against armor and the tank gets armor cover -2 ( we are assuming that the infantry is not stupid enough to try and assault the front part of the tank that is most heavily armored). Engineers get to roll an extra die when assaulting tanks since they are better equiped with explosives. Once the assault is made, the defenders attack back (assaulting units get no cover). Surviving assaulting units return to theri previous hex or remain in the assaulted hex if the enemy has been eliminated. With the ambush rules we use assaults are not always simultaneous. We find that with the ability to assault tanks the opponent is much more careful with how he uses his tanks and vehicles and tends to protect them with his infantry.