Why not make them function similarly to Devil’s Ruin? In this way, their ability to hit for critical damage would allow them to have a more defined damage niche in PvE as well as more perk variety. And in PvP, it would solve one of the fundamental problems with fusions as an archetype: consistency. Rather than keep fusion rifles operating with an inherent degree of randomness, randomness that naturally discourages roll diversity by funneling players into two stats that have the potential to ruin the sandbox (looking at you Main Ingredient), this change would keep them deadly and consistent but would require steady aim to reach an optimal TTK, placing greater emphasis on gunplay and less so instant kills at 20 meters. Additionally, it would allow for more distinction between the archetypes rather than having a best in slot (again, looking at you Main Ingredient). Just food for thought.