What is the reward for the Imam who generally leads people in prayer, and specifically what is the reward for the Imam who leads people in prayer and delivers the Friday sermon?

The reward for leading prayers (Imamah) is great, and delivering the sermon (khutbah) alongside the Imamah brings even more reward and recompense. This is because the sermon usually includes admonition, guidance, and an invitation to goodness. The one who calls to goodness receives his reward in addition to the rewards of those who benefit because of him.