Other than the fact the Villanova played 3 forwards most of the time last year, that is a great point.
But they played forwards who could shoot. Calhoun was woefully behind the times when he tried to shoehorn Drummond and Oriakhi into the same lineup. That kind of early-90's basketball is dead. And I say that as someone who grew up watching the Ewing/Oakley/Mason Knicks.
You need 1 rebounder/rim-protector. Let's say you have 3 guards/wings on the floor.
The question basically boils down to: who do you want at the 4? What kind of player gives you the most marginal impact?
A) Another true big who isn't a threat from beyond the foul line
B) Another bigger wing type who can shoot and handle it a little
Ideally, you'd get a Draymond Green type who can defend true bigs, while being a threat from all over the floor. But if you have to choose, A doesn't give you very much -- there's only one rim to protect and one rebound to grab. That kind of guy at the 4 helps the opposing defense much more than your own defense. B is much more of a threat, while not giving up much on defense.