Anytime you can get more than 0.5 cents, do it!

There are London hotels asking 200 GBP for tiny rooms with a single bed. At 50-70K per night, that might work out fine on a $ per point basis. But I'm not chain-constrained, and so I'll go stay somewhere nicer or farther away from the centre - therefore 200 GBP isn't relevant to what I would actually pay.

I now just hang on to a handful of CC points to use in places where there isn't much alternative or where a hotel falls into Category 1-3.