I agree, I think that one of these things has to be true to get good value -
1. A high point redemption (like 80000/night or 95000/night) where the normal cash cost is high (i.e. Conrad Maldives, Conrad Tokyo, etc.)
2. A redemption at a time when the cash cost is abnormally high but there are still award rooms available at the standard rate (i.e. Doubletree Times Square on New Year's Eve).
3. 5th night free - won't get great value normally but will at least usually get the .45 to .5 cents per point value.
4. Any 5000 point redemption (think Egypt or Turkey).