For lower light corals zoanthids are a great beginner coral that could adapt to lower and higher end lighting. You would have to tell us what specific lights you have to get more specific reccomendations.
They will snap at both of those to get them out or away from the cave. If the Hermit or Snail keeps going into the cave the Pistol Shrimp will kill them. Usually they back off right away once the Shrimp starts snapping at them.
This is just my personal experience and observations.
so a tiger pistol shrimp and yellow watch man goby should pair up and leave snails crabs alone if they dont mess with him and theyl leave a firefish alone