Direct injection will carbon up the intake tract if idled excessively. Not an issue with port injection. One of the reasons my F150 is a 5.0 and not an EcoBoost 3.5, since it is my wife's DD and mostly does short trips under 5 miles, barely getting warmed-up.
The new 7.3's basic engine architecture, right down to the coil pack locations and shorty wires to the plugs looks like a copy of GM's LS motors. Not necessarily a bad thing.