When im in a MRLS (MLRS) - i always fire at sniper holes and tunnel openings -- sometimes i get rewarded with a "Boink" -

Plus - if i see a red streak coming from somewhere - i pump a couple rounds the way they came... sneaky snipers....

and if you have your MRLS behind the tanks - shooting long distance (works with MA too!)
you will find your tanks have a better go at it.
And your protected from enemy fire a bit...

of course when the air units come out -- a different ball game.....