WhAts the dad build? Asking as a dad!
The idea is things for people with slow reaction times. Instead of the typical 17 year old pimple faced shotgun/hand cannon twitch reflexes ape. So mostly, in the current meta, pulse rifles...not sure about Jotunn or Hammerhead. I'd say Coil is more in line for the heavy.
That said a couple things so I can get my shots in at the hand cannon hegemony, first, the meta is really about whats balanced to be GOOD more than anything. In the pulse meta (all three months of it three years ago) good players were rocking Nerwins or Hopscotch Pilgrim. Not because they had slow reaction times, but because those were the best guns! Similar to how Luna's/NF is simply balanced to be the best guns right now, not really anything else. Although, I get the point about slower reaction times and rifles. Even I, who am pretty slow, can tell I'd be at my best with my Luna if I dedicated some time to it, because it's really strong.
Second if Pulses are Dad, that makes Hand Cannons SON. That's right they're SON cannons, lesser status cannons, so to speak. Pass it on. You got sonned.