As axis I like to spam medium tanks+interceptors as my offensive units.

For defense infantry+anti-air.

Attack bombers if the enemy have heavy tanks.
Heavy tanks for defending of another medium tank army.

If the enemy like to hit and run with artillery I always prepare some paratroopers to slow down the enemy and then catch the army with my medium tanks

Motorized only use them early if my country have 2 rural food province, later i use them independently, taking unprotected provinces or if the enemy began to produce a lot of anti-tank.

There's no secret formula.
You adjust to the enemy, to the terrain, and to your resources.

Maybe the enemy is a heavy user of AT guns.
Maybe you're surrounded by forests and mountains.
Maybe you start without any rural oil provinces.
In these cases, it would be foolish to build armor units.

You must adapt.
If you try to follow the same recipe all game, every game, you will lose.

Besides, 2 AA guns is never the answer.
Most of the time, you're not facing any air power, why bother with AA?
It's just slowing you down, and decreasing your attack power.
If the enemy is an air power expert, 2 AA guns are not going to help.
You'll need HEAVY AA cover and/or interceptors.

When I see someone with 1-2 AA in every stack, I know it's going to be a quick war.
Slow stacks moving at AA speed, sitting ducks for my artillery.

6 heavy tanks 4 sp anti air. All blueprint. Add in an artillery for range or an armoured car for scout if you want

this would be my advice for an basic axis army, in which every troop has a special bonus given by the doctrine
for terrein:
medium tanks:
(-1/-2 day of availability)(+30% health +15% damage)(because of axis)
motorized infantry:
(-1/-2 day of availability)(+15% speed, +15% damage, +15% damage against infantry)(because of axis)
anti-Air:
(-1/-2 day of availability)(+15% damage, +15 health)(because of axis)
railroad gun:
(-2 day of availability)(+10% speed,+15% damage, +15 health,+10% attack range )(because of axis)
for ocean:
submarine:
(-1/-2 day of availability)(+15% damage, +15% health, +15% damage against boats)(because of axis)
for air:
rocket fighter:
(+15% damage, +15% health, +15% speed, +15% damage against airplanes)(because of axis)
attack bomber:
(-1/-2 day of availability)(+15% damage, +15% health, +15% damage against infantry/heavy armor)(because of axis)

The guy was asking about a stack. Are you seriously suggesting to stack mot.inf and med.tanks with railroad guns??

I think he's just posting a text snippet of wiki.callofwar.com/wiki/DOCTRINES

The real answer is for everyone to have wiki.callofwar.com/wiki/DOCTRINES in a side tab

Did I mention that wiki.callofwar.com/wiki/DOCTRINES is useful?

Yeah, please refer to wiki.callofwar.com/wiki/DOCTRINES

I was just telling the strongest troops of axis, nothing much, and yes I took a reference from wiki call of war

You know what the realtors say "Terrain, Terrain, Terrain"