R.U.S.E.

For this cheevo you need to change the profile of the AI to each of the following :

Regular (that is default)
Airforce
Howitzer
Prototype
Blitzkrieg
Turtle

For every one of these I did the following :
USA for myself
I picked USA for the AI
Picked the map BLITZ

I then start off doing the following :
I initially build an airport before anything else. Then I blitzed the 2 sections where my base is and the one just to the left and slightly above. I put down supply depots by the base, the next one slightly up to the left over the river and then a far one on the left side. They are all accessible by the main road that leads over the river to the left of your base. As soon as the airport is built research the paratroopers immediately. Then you need to be quick on this next part. Prepare yourself to drop 3-5 paratrooper units over near the enemy headquarters and their supply depot. About 75% of the time they just started a construction of an airport as my guys were dropping out of the planes so I was pretty safe landing them on the ground and capturing the headquarters and their newly constructed airport. Grab the supply depot as well then make some bombers that can take out the rest of the scattered soldiers and maybe a tank or 2. Each time I did this playing against the 6 different AI profiles I won the match in about 7-10 minutes. You can do basically the same thing for the TROOPER and AMBASSADOR cheevos as well.

If your not quick you will more then likely get your paratroopers killed before they land or right as they land. If that is the case just create some bombers and take out the enemies near the HQ (or restart the mission!). Once you have the HQ it is easy pickings on whatever is left to destroy for a total victory.