This is the same absurd neocon idea that getting rid of a dictator is the solution to everything.
Removing Ayatollah Ali Khamenei would most likely bring a military general to power, and they are cut from the same religious cloth, so there is no guarantee that anything would really change.
The possible U.S. intervention in Venezuela raises the same problems as Iraq, where they removed Saddam and never considered that:
1. He kept the crazies in check, so we got ISIS.
2. He was the number-one enemy of Iran, and removing him benefited Iran.