SU-25T frustrating Campaign

On mission 12, I have to help out the ground units advancing. The mission is very frustrating in many ways.

1. I have no LOS on enemy SAM because they're behind a large building but they can shoot me.

2. I have to clear all enemy units or I fail. I managed to kill 7 out of 8, leaving just 1 armor and I am to report for court martial. I thought I'm supposed to "Help" the ground units not do all the work?

3. Unrealistic time. If I don't clear all enemy in 3 passes, mission fails. And 3 passes is not possible due to all the buildings and trees. I even ignored all the WP and went straight to IP and still not enough time.

4. Stupid wingman. I don't think this needs any explanation. For other missions, I just park him until I clear all the SAM and then tell him to attack. But for time critical mission like this, I ask him to help and goes down rightaway.

Started playing again in about a month ago and already not enjoying it.

I just said hell with this and turned on immortal and unlimited ammo to get over this. Even with that, I barely cleared it in time.

Wow, the campaign is really pissing me off. Now it's Apache that I can't shoot down. Its flare fools all my and wingman's missiles and if I go in close for guns, it shoots Hellfire at me. I avoid the missile and come around and it fires another. I do that for awhile and the ground units go in for suicide and I fail the mission. If I ignore the Apache, they kill the ground units and I fail. Even tho the ground units have SAM, they wont shoot at the Apache.

Did they design the missions to be frustrating on purpose?

I got it done by using unlimited ammo and shooting 7 R73 at it. It does not feel good to cheat.