Super747

Lets continue tweaking Battlefield 2:

Tank:
A good add to the tank I saw in POE2:
1 Guided Missile.
2 Canister Shell (convert your tank in a giant shotgun)
Also in POE2 they add some smoke when you fire the main cannon, this make the shoot more realistic and looks more powerful.
Make sure your tanks has at least 2 types of munitions: AP rounds and HE rounds. (Like in AIX)

Vehicles in general:

Remember, is always better one vehicle with multiple munitions, than various vehicles with 1 or 2 types of munitions.

1 vehicle with multiple types of ammo = multiple tactical options = fun = good mod
1 vehicle with 1 or 2 types of ammo = poorly tactical options = boring = bad mod
Multiple vehicles with 1 or 2 types of ammo = poorly tactical options = boring = bad mod
Multiple vehicles with multiple types of ammo = multiple tactical options = really funny = OUTSTANDING MOD

Music!
In AIX you can turn on the radio and listen some music.
Also in Alpha Project, in Pripyat map has some ambient music. The music from COD MW 1, that's is a nice detail!

In the air:

The slight movement of the cabin in SOW2 make the piloting experience more real.
If you think that the Minigun of the A10 in AIX is little bit exaggerated, you can use the Minigun of the A10 in AIX MiniMod, also in this mod the machinegun of the jets in general do a lot of damage and overheat very quickly, forcing you to think when pull the trigger.

Smoke:

The smoke should no disappear so quickly. This increase the chaos in the battlefield.

REMEMBER!
To make a good mod, keep in mind:

1 Nametags: Use the system of Alpha Project
2 Sound: this is VERY IMPORTANT.
3 Effects: Improve the effects of explosions, countermeasures, etc. (even a slight improvement change lot the game)

Littlebird:

In POE2 the Littlebird has a turret for the co-pilot. This is a really good complement for this chopper.

Arcade Vs.. Realistic

Maintain your mod semi-realistic. If you made it arcade, becomes boring. And if is to much realistic, becomes tedious.