Currently, I'm not sure if its possible to exploit this in any way (e.g. using a Puma to pop smoke on a tank at the right time, or something)
That would be really clever, if it's possible.
Tall buildings and hills can block the rockets. The town & hills at the NE part of Rails and Metal, for example. Of course, that relies on the planes coming in at a bad angle

The AA halftrack got mentioned, and the Ostwind is really good at shooting those planes down, also, if you have it available (teammate or doctrinal). Just make sure the Ostwind is not moving, so that it has better accuracy.