I would suggest being able to toggle between launch and set depth, in order to fire from behind terrain and steer the torp over the feature, and perhaps have it go back down.
For speed, the ability to run the torpedo out at max speed, then slow to search (especially for passives) to improve sensor effictiveness would be very helpful. Ideally, a torp that acquired a target while being used this way would accellerate to the maximum speed it could reach without losing its sensor lock on the target.
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