Need some major advice...

The last three are much better and can be cleaned up in PS. The first two are to far gone they're not worth messing with IMO.

My experience that Headshots can take PS'ing and even have makeup, but it depends on the receiving organization and what they want. Most expect some work, just keep them natural looking and you should be fine.

You're doing better with light but worse with posing. Keep his head straight or a slight tilt toward camera looking downish - females look good with head tilts away from camera but guys generally don't.