In the stand-up comedy top, there's room for everyone - if you're good, there's room for everyone. You'll put on your own show - no one casts you. You cast your own show as a stand-up comedian. When you get good at stand-up comedy you book a theater and if people show up, people show up. If people don't show up, people don't show up. You don't have a director or a casting agent or anybody saying if you're good enough - the audience will decide.