There is some truth in the fact that a half wedge hole can be scarier than a longer par 3 hole. At Fortune Bay, we discussed making the tee placements for the back tee (155 downhill to a platform green) up on the shorter tees (130, 110, etc.) from time to time just to make club selection and swing strength less automatic.
The downsides are that with greater length by good players, there are already too many wedge approaches to greens these days, so if par 3's are a great chance to introduce variety and concept shots, just being a short hole is less attracive than it used to be. Even less so with Dave Pelz, gap wedges, etc. that make the half wedge more of a mechanical, standardized shot than a feel shot than it used to be.
However, on a par 3, at least you can control the approach length for all players, whereas even on a short 4 or longer 5, some average players will be approaching a green designed for a sub 100 yard approach from 180! There are also some practical problems - ball marks on a hole where every shot will be a high, high spin shot - so its hard to make it a smallish green suitable for that shot.