I just switched this spec to arsenal.. way better, more damage, and I use unload a lot also, dmg increased + slow, does about 2.5k per last tick on full bm gear.
5 stacks heatseeker hits about 4-5k crit, tracers are 2-3k crits also pretty nice.
shield on tracer cast handy, no interrupt handy, rocket boost and punch also handy.
I'm not going back pryo until they buff detonator and make this tree's skills a bit more helpful in defense.