Narrow Green entrance for sure. While I hate the 14th on Trails (less due to philosophy and more execution and severity), that sort of philosophy is appropriate for short driveable par 4s. Also like 14, a green with a lot of slope bordering it makes a birdie, even if you do hit a good shot but not a perfect one, anything but a foregone conclusion.
Also if the topography doesn't allow the above, some trouble well short of the green (be it a pot bunker that the fairway funnels towards, shelves or severe humps and bumpse, or maybe a very narrow landing area) gives challenge to those that choose to play extremely conservative on these types of holes. There's got to be options but I think short par 4s that allows mindless hybrids/irons and then a gap wedge approach don't put enough value on par.