Zombie Type Toggle

I'm sure that this has been discussed previously, but what would the general consensus be of having a natural zombie type toggle to be included in the game?

I'm personally a zombie purist, and would prefer to fight larger hordes of regular zombies, but with the oddities (cops, screamers, wights, spiders, etc...) in the game, I tend to turn down, or keep the spawn percentage at the norm.

Would the ability to select what can and can't spawn be a boon? Or a bust?