A show with Mike sighing and doing goon work.You buggin.
A show about a Mexican drug cartel would be straight piff breh.
He doesn't have as rich of a life to work from as Jimmy does, plus he's already lived most of it.
Jimmy was the perfect choice.
Gus is too "plain" to carry a show as well, and he's too old to do his young years which would be him doing evil shyt with the Pinochet Regime.