In A New Hope, the Rebels apparently had their torpedoes programmed in advance to head for the exhaust port and then turn downward into the shaft to the reactor core. All the pilots had to do was activate their targeting computers, and they were ready to begin their attack runs.

I base this on the fact that when the fighters entered the trench, they were far to distant from the target to be able to "paint" it for attack, and so I believe the computer "knew" in advance what to hit and the torpedoes only waited to be armed and brought within range before they could be delivered to the target. In addition, there's how the torpedo runs straight ahead and then dives into the shaft, as if someone's told it "go straight ahead until you're above the port at co-ordinates a-b, then dive into target and proceed to the reactor at coordinates x-y".

So could it be possible for a Commander to enter the map, zoom in on a certain location, and designate it as a proton torpedo target? In essence, this would mean that if you as a pilot set your torpedoes to Guided mode (as opposed to Dumb-fire or Homing), they'd make for their programmed target upon being fired, either going straight there or doing something fancy like going straight forward, maintaining altitude and course, for then to dive on the target. Of course they'd have to have a certain level of inaccuracy so that they'd be true to lore (two metres wide targets, which would encompass non-AT-AT ground vehicles, apparently could not be easily hit) and not over-powered.

I think it'd not only encourage mobility and cover, but also make for some nice team-work, akin to how the laser-carrying Special Forces were to operate. One way such an attack might happen would be:

     1. A scout platoon spots an Alliance infantry fire team and a T-3b Tank in a narrow valley, guarding an important bridge. They radio in their discovery the regular way, with the Commo-Rose's "Spotted" command.
     2. The Commander zooms in on the spot on the map, right-clicks the location of the tank, and chooses "Torpedo Attack" from the list of options that appears.
     3. The pilot of the map's TIE Bomber, circling behind friendly lines waiting for a target, is automatically notified by means of text message, warning tone, and map icon. He switches his proton torpedoes to Guided mode and heads for the bridge.
     4. Once within range, he fires three torpedoes, one of which gets lucky and spears into the Rebel tank. The blast kills the tank as well as the infantry units using it for cover. The bridge is now badly under-defended, and the Imperials are free to advance.

Of course this system might not be possible, at least not without a workaround, but I think it's a good idea, leading to a "take your vehicles into the open at your own risk" type of scenario. Come to think of it, proton torpedo salvos could also easily replace the Commander's Artillery ability on certain maps .