14 gallon freshwater stocking?

Hi, mollies grow pretty big. I wouldn't add those. Guppies aren't a good choice because of its fancy tail. The betta will think the guppy is another betta and attack it. You can get one oto. One should be enough to manage algae in your tank. Don't be surprised if it dies. That is the hardest fish to keep alive. I would add a trio of cories. My favorite are the panda cories. They are very interesting fish. You will not regret getting them.