Crowne Plazas occupy an uneasy slot in the wide space between Holiday Inn and Intercontinental, usually much closer to HI's in terms of service levels and facilities - though room prices may suggest otherwise. If you couple that with the totally underwhelming recognition afforded to any of the IHG "elite" levels (RA apart) and you have a recipe for disappointment.
All in all it's an odd brand. In the US Crowne Plazas seem mainly grim, in Asia they can be quite lovely (Doha and Chennai were my recent surprises).