Ranges of 5KM? Not the airborne variety, at least not very often (while the torpedoes could run that far, they weren't guided and the objective was as short a run as possible, contingent on arming the torpedo and giving it enough time to reach the correct depth).
Even late-war torpedoes were more like 3KM or so, tops (factoring in airspeed and air travel). And while 1KM was "in AA range", it wasn't the face-hugging approach that dive-bombers used; we're talking very different animals here, especially once we get into late-war torpedo bombers, where they weren't basically sitting ducks, coming in on the deck at 230KPH or thereabouts.
Anyhow, I think what you're forgetting here is that IRL, a torpedo wasn't going to get hit by flak at all, generally; every once in a while, somebody would kill one with a HMG, but that was
rare; it was lot more common that they'd simply miss. If torpedoes acted more like their WWII counterparts, where dodging was the best defense but they weren't terribly accurate, then the dynamics would be considerably different. I may try setting up some torpedoes to do that in Vacuum, actually, just to see how that feels
Torpedoes aren't really the problem, anyhow; the difference between them and Atropos is fairly substantial. I'd argue that Daggers are almost, kind-of worth buying, if you're going really fighter-heavy, but Tridents? No way.