Gave your reasoning for this please. How are Axis units underpowered.
A few of the more obvious points:
1) Infantry. Especially Phase A. It costs more and, while those infantry MGs may work great, most infantry casualties are either at close range, are from arty, or are from vehicles. They also lack vet. I haven't done extensive testing, but rangers support feel more effective than PzGrens and are cheaper. Strosstruppen are nice, but that's the only German infantry squad which actually competes on cost-effectiveness with the allies (except perhaps Ersatztruppen). This isn't fixed in B or C. You do get cheap infantry commanders though, which is nice.
2) Tanks. Especially in Phase A. The super-stug and the firefly are all well and nice, but you only get one. Once it's located, it becomes very hard for it to actually score any kills. The enemy just sits back behind cover in that area and moves forward everywhere else. You're weaker everywhere else because you've spent points on the tank. Allied options are more numerious and often more useful. If you can get SS Panzer rolling they'll have the advantage in later phases, and the other German divisions aren't awful once you get past A.
3) Air power. Especially in Phase A. Allies just get more.
4) Support vehicles. Only SS Panzer get any good ones as Germans. Luftlande get French tanks which are expensive, and not very good. 17 SS get SPW 221s which can do fun things, but only against other vehicles, and SPW 223 command vehicles which are kinda expensive to use as infantry support vehicles due to their command aura. Being able to direct anti-infantry firepower to where it is needed is really useful in A, and allies just do it better than Luftlande/17 SS.
The Germans advantages in A? 12 SS Panzer gets awesome infantry support vehicles. Luftlande get off map arty and spamtruppen. 17 SS get... huh. Come B and C the allied advantage drops, or even turns to Germans, but if you're coming out of A with a worse kill-death ratio and +1 victory point a second ticking in for the other guy, the counter attack is hard. While the Germans get cool stuff from B (hard to crack Panzers, Luftlande air power, nebels), and this cool stuff will often turn the tide somewhat you need time to recover, get the amount of troops on-field back to roughly even, and then take ground. I find I have "comebacks" a lot more with Germans, but it's usually too little too late.
Now - it's worth bearing in mind we have two infantry divisions on allies, and these two divisions are often cited as being the strongest divisions. Germans have no infantry divisions. This may simply just be an issue with the way that infantry divisions are designed: they have cost effecitve infantry and light support, and cost effective infantry and light support wins you Phase A.