Alpha+3 changed several things that I think make the game better. Some may say it didn’t go far enough, but that’s what house rules are for :-D
The biggest change from OOB to the alphas IMO is how airbase scramble works now. Limits of 3 planes per airbase, and being able to scramble from coastal airbases is awesome if you haven’t used it that way.
The highlights for Alpha+3 that changed from Alpha+2 are:
*UK naval rearrangement around England
*Italian ships moved to sz96
*Air bases striped from Gib & Malta (no air cover for allied ships w/scramble in Alphas)
*AA guns are limited to 3 shots, and can be taken as a casualty (makes them more like a unit now IMO)
*Mongolian rules added for Russian/Jap Nap
*Bombers added to Germany, Italy, and UK
*Tweaks to convoy
*Tweaks to SBR (strategic bombing runs)
*Minor NO tweaks for several powers
*Anzac going after Italy (doesn’t make much difference in Pac, but could in the Med with bigger Anz presence).