The Garrett .44Mag loads for Super Redhawks appear to me to provide everything necessary for this functional class of load/gun?
A good 330 doing 1,400fps with 1,400ft/lbs of energy seems to be as much power as you'd need in a handgun. More than that strikes me as insane. And because it's a .44Mag you've got all kinds of flexibility for lighter stuff, personal defense loads, etc. Plus there's speedloaders available, which isn't the case with the .480 and may NEVER be, given how close together those case rims are!
At present, I don't need anything with this sort of horsepower...but when I do, especially since I'm not a handloader, this seems the best all-around combo.