Hi monge_4,
Seems you have a few things you might need to sort out, seperating the fighters for one...
But your main problem being that you dont want to be overrun by baby guppies? You need something pretty docile to eat the babies, not predatory, guppies are notoriously bad with predatory fish (adults especially) as anything predatory (like the more aggressive tetras or Butterfly fish) are going to eat your adult guppies.
Like someone else said, if you can't cope with the enslaught of baby guppies, you are best not breeding them, keep all males.
Or that aside... the fish you would want would depend hugely on what size tank you have!! Cory catfish are great for snaffling up new babies or small species of loaches (schistura species aka tiger sand loach or tri band sumo loach) or Rosy Loach.
Cherry Barbs might be quite good too because they dart in and out of plants and live fairly low in the tank.
What size tank do you have?