Most often, the graveyard is the least safe place to store our creatures. So being part of the cost gives us an uncounterable way to pitch our creature, but I'm not sure in what situation that would be applicable. I'm just seeing it though the eyes of giving your opponent more options, more information when they have priority. If you cast
Collective Brutality and pick two modes, discarding Griselbrand, you pass priority to them with a spell on the stack and a juicy creature in the graveyard. Compare that to casting just
Careful Study, all they know is I'd like to draw 2 and discard 2. Maybe I'm digging, maybe I'm binning a creature to go off. They have to decide to counter or not based on less information than Collective Brutality. And if they do counter Careful Study, then I'd feel better not passing the turn with the creature in the graveyard. It's as if I want to advise considering using the Escalate function as a "fringe use" up there with Thoughtseizeing yourself, which sounds totally ass backwards, but in a lot of instances I want to use it, it doesn't work. I can't kill a DRS and bin a creature. I can't rip a Surgical effect out of their hand and bin a creature. Only time it does work is when they're on a single counterspell, you'll get to bin the creature, force them to counter or lose it either way, then the path is clear to reanimate. Which is on par mana-wise with Duress into Careful Study into Reanimate, so I'm fine with that. But all other uses become really expensive for what you're doing. I actually like Collective Brutality better in my Storm lists, opening up lines with
Infernal Tutor that would normally be dead without a LED. But then I don't really care what I'm discarding, it's just flak that I can't cast that turn to get Hellbent.
Green is pretty much just to power out Abrupt Decay. I also run that single Pernicious Deed, but other Storm-y sideboard cards like Swarm and Carpet of Flowers don't really get used here. The red for Izzet Charm isn't really a problem, sometimes you do have to be nimble with your fetches and how you tap, but if they weren't red duals they'd be a basic Island and Swamp, so everything would still apply there. Honestly, their main function ends up being pitching to Force and cards to swap out in sideboard games. It's rare that I'm actually casting them, but what keeps bringing me back is whenever I do, it's always super useful. EOT burning their DRS, EOT drawing and discarding to set up the reanimate, or rarest is actually mana leaking someone. But my games do tend to grind, so it's happened before. I'm not so much advocating for them as I am explaining my own preferences.