Yeah, as someone who has to sit with the RNG for the KB 3 man every raid it is ROUGH stuff. It is nice to have it down with so many other maxed teams as well, but it isn't necessary unless your guild is really pushing. I have Bariss R9 for a TB op, so I use her and the RNG I need is way worse because of that, which is a choice I made that I still don't know if I stand by.
Tarkin/Skorch and JMMW are so good and so quick/consistent that there's almost no reason to build other stuff unless your guild needs it. BB2 as well unless you plan to R9 them. I HATE them at R7. it isn't the worst thing ever but it always takes me at least 3 or 4 attempts, sometimes 5x that if you're in a bad set of seeds.