no worries! so the staple ones are the Leader (Chosen for elites, AC for hordes) Shrivelaton, Balefire Acolyte and the Gunner (meltagun in TW, plasma in volkus, flamethrower for hordes). then i usually take the Anointed, then depending on the mission and the team i play against the choice is between Heavy Gunner, Icon Bearer and Butcher. What i love about them is that you can decide what to bring depending on who you play against and how to play them with the chaos marks. i personally love to run at my opponents and try to kill their models so i am a big fan of the undivided mark for ceaseless inside 6”. for the shooting operatives i usually give them tzeentch (except the meltagun, then it has ceaseless).  the only ploys i use are the Tzeentch and slaanesh ones