I'm looking for a big handgun that's also well balanced (not muzzle heavy).
Muzzle heaviness is a desirable quality for steady hold. That is why some handguns (and rifles) used in Olympic shoot events have weights attached to the barrel. If the gun's weight is mostly in the shooting hand, the gun (sights) wanders all over the place. That is why a lot of modern revolvers have solid under-lugs. Shoulder a Kentucky rifle and note how the sights just seem to hover on the target...that is due to the weight from the very long barrel. But, if you insist on the majority of the weight in your hand, just get a revolver with a four-inch barrel instead of a six-inch or eight and three-eights inch barrel.