Seeing a number of par-3s mentioned here (and nominating two myself!), I must ask the question: is there a bad blind par-3 that you have played? If so, which is the hole, and what made it bad or uninteresting? My guess is it depends largely on the green complex and the interesting shots, stances and putts that can be had once nearer to the hole. However, in every case I can think of, the blindness adds to the strength of a hole, it never hinders.
One such par-3 that I have in mind is number 4 at Dunaverty, where you play over the crest of the ground to a sunken and bunkerless green at the foot of a large hill. I really enjoyed it and although I wouldn't necessarily categorise it as great, I would say the blindness certainly contributes to its otherwise average qualities as a hole.
While variety is the name of the game and I wouldn't want to see every par 3 blind (just as I wouldn't want to see every par-3 as a biarritz), very few times do I encounter a blind par-3 and not get the tingles. To me, the blind par-3 can delay gratification and heighten anticipation. In a world where instant gratification is king, isn't it nice to have some of that gratification delayed, if only for 3 minutes? By this nature, is the hole not great on the merit that it excites and intrigues? I suppose most arguments against the greatness of the blind par-3 hole start and end with fairness and individual scores...how utterly boring.