Aerospace take a control roll in atmosphere if they take damage at all. That means more hit chances are better than big damage if you want to cause a crash. It is also helpful to have enough range to engage fighters that can be on the low altitude map, where additional distance is added for each level of altitude.
Since field guns have a minimum crew size, it is also helpful to use multiple smaller guns to remain effective when taking damage. It takes less damage to silence an LB5 than two LB2s.