This is not so much a top-end DPS weapon as it is a utility, DoT weapon. Group enemies up, status them to hell and back, and open up with melee and abilities. This bow can and will burn down high-level enemies with enough shots and time, but doing so wouldn't be playing to its strengths, IMO.
[Galvanized Aptitude] only applies to direct damage, not radial attack damage, so [Serration] and [Heavy Caliber] are used instead. Some use Primed Firestorm, but I just don't see a point when the tendrils pull enemies into the already-adequate explosion radius. I've tested Primed Firestorm, and it doesn't extend the explosion much past the group of pulled-in enemies.