If your struggling with CMSF, like i was for a long time, then this was my "ah-ha" moment when fighting in cities.
Give your troops lots of Javelin missiles and put them in 1st/2nd floor buildings (never the roof), watch them take out the enemy armour.
For tricky targets i have used the sneak/slow command to bring them close behind a tank.
Once the armour is destoyed THEN move your Syrykers forward.
Try this on the 2nd or 3rd mission (the one in the city). You will see how powerful ATGMs are and why you should use them.