Is there anything stopping me taking both a CGC icon AND a cult icon? One on a cutter and the cult ion on the leader? And if I can does that mean my leader could activate 4 others if he has the Commanding Presence skill?
Nothing stopping you taking both and yes the effect of cult icons and commanding presence stack. The downside of that is you have to have 5 models in a 3" bubble to pull it off, which is asking for the opponent to put every template they own on you, and if you're bringing Corpse Grinders you can guarantee your opponents are loading up on every Blast weapon they can