I don't think the Typhon needs much. It's incredibly powerful even inside its minimum range, at least on a Galleon or Spire. It's pretty much useless on a Goldfish, simply because they nerfed Explosive (.3 from .5) so it can't deal with Armor very well.
Something we could do is increase the minimum range to 350m or so, and then make the arming time a linear dropoff in damage; its hard minimum range is 150m where it deals half its damage. Then, the closer you get to 350m the more AoE damage it does, until it deals full damage at 350m. This would make it less of a binary thing, as much as it wouldn't make realism sense at all.
We could also shift damage from its AoE to its Direct damage.