I've asked before, and Hertz points can apparently be very good value if you find yourself in need of a rental car in an expensive market or want a one way rental in a place Hertz isn't crazy about adding to the local rental car inventory pool. Iberia Avios at 3K Avios points per $100 e-Rewards can also be a good return rate if you can get their award chart to work for you.

This is assuming you've got the airline/transportation award options as well as the hotel awards.