Auto supply, air back to base, replacement rules makes the game less challenging than PC1
 Logistics always play a major role in warfare. Automatic resupply effectively removes logistics as a factor in the game. This makes the game significantly less challenging. In PC1 a unit had to get out of an enemy’s ZOC and spend a turn to resupply. This made the game much more interesting from a planning aspect – attack or not, defend or not. Right now you can do both with no supply worries.  AC back-to-base rule also dramatically weakens the PC2 in 4 areas: 1. Right now never run out of ammo or fuel; 2. Ability to linger over targets lost; 3. Fear of running out of fuel lost; 4. Ability to attack a ground unit with 2 AC lost.  Ability to “fully” replace within enemy ZOC eliminates critical decision on whether to hold hex or not. I believe in PC1 if in ZOC of 1 unit then only partial replace allowed. If in 2 units ZOC, no replace allowed.
Recommendations (as a minimum)
Put in option to use the PC1 supply rules for following: Overall supply (must be out of enemy ZOCs).; AC must be flown back by decision of the player, not automatically; levels of replacements subject to enemy ZOC limitations.