[freyrs3]

> you gain almost nothing from Haskell, and you might have been better off writing your code in another language.

Don't know about that. Even if you write everything in the IO monad, Haskell is still a pretty great imperative language and many people say it may possibly one of the best imperative languages ever written.

If you only use IO, then yes, you no longer gain the ability to reify and isolate effects as values but all the other strengths of Haskell's type system mostly remain invariant and just as useful.