Could have further explored Hirogen culture and added an aggressive voice of agreement with Janeway. Spend a couple episodes looking for his lost son. Make him a security officer to butt heads with Tuvok. Though, I will say that Seven had enough mentors to choose from by that point.
VOY s6e15 “Tsunkatse”
This sort of thing would’ve made Voyager an all-time great series: just having them sort of accrue crew members and even whole ships as part of their fleet, and rolling back into the Alpha Quadrant with Amelia Earhart as acting Captain of the Equinox and this Hirogen as her security officer, and like two versions of a couple of characters (after the “Deadlock” episode), and Neelix and Tuvok and also Tuvix, and maybe a Borg sphere operated by several of the liberated Borg they came across during the course of the series, and some of the allied ships they hung out with during “Year of Hell”… Honestly, it would’ve made the point about how awesome the Federation is even more poignantly if they kept gathering more and more people who wanted to be a part of it.
Would also help account for all those extra torpedoes that were pulled out of thin air.