When looking for alternative terms for the phrase "goofy loony," there are several options available. One such term is "zany," which refers to someone who is eccentric and unpredictable in a humorous way. Another option is "kooky," which suggests someone who is unconventional or odd. "Whimsical" is another term that can be used to describe someone who is unpredictable or lighthearted. "Offbeat" can also be used, referring to someone who is unusual or quirky in nature. Lastly, "quirky" is a term that denotes someone who has an unusual or peculiar personality that is often amusing. Overall, there are many words that can be used in place of "goofy loony," each with its unique connotations and nuances.