Movement: Since only artillery units have range, all other units must close to engage the enemy. I considered Movement to be just as important as Combat Factors is units with higher Movements would dictate when and how that CF is employed.
Combat Factors: Since this is simply added to a d6 roll I made it a straight line progression.
FP: The more FP the longer a unit can stay in the fight, but since these are expended and only replenished if a supply die roll is successful I decided not to give them any more weight than the above factors.
Range: In a game where most units don't have it this is a major factor. I decided on a division of 3 for ease in calculations. I also decide to make the player pay for the number of artillery shots as a way to keep ranged units in line.
Requiring HQ's with Armor, Arty, and Recon units to pay more takes into account the added logistics needed for these units without a lot of extra record keeping.
Point for point AT Guns are more expensive to buy, but can make units much more effective vs tanks.
Cavalry: I reduced the FP for them to 3, but allowed them to attempt resupply anywhere on the battlefield. I think this accurately reflects cavalry in WWII. If they stood up and fought they were quickly decimated, but if they used hit and run tactics behind enemy lines (think Cossacks) then they did quite well.
If you have any more questions I'd be happy to go over them.