Check airfare. My airfare to miami in march would be over $1400 during spring break. I'd pick Miami if airfare is reasonable. Hotels will be high in Miami, but check. I'm flying in for oasis.
Galveston hobby is closer, 45 minutes, sw flies there. IAH is farther and shuttle is more. Mama mia was fabulous.
I'd check airfare and hotels. I'm flying march 11 to miami.