There should be a better aim for the Rocket Truck, its the future im sure they have a drone or something to look further or something like that, the range seems very limited just because i cant always look that far. alternatively you could enter a 'deployed' mode ad then aim it without seeing the target by mil and angle calculations similar to stuff like Hell let lose or something like that. but the angle i am able to get out of them on average seems pretty poor.
To counter it The AA turrets should be able to Catch these rockets, maybe not 100% of the time but it feels weird that they cant defend them already its not that small and should be defendable by them.