We all miss the FirstPremium magic coach number 9...
About the Carte Blanche: well, it gives Lounge Access, which anyway I already have with a BusinessPremier ticket or with my AMEX Platinum card.
Priority ticket desk: used once.
Fast-track check-in: not that different from non fast-track check-in (especially when Waterloo Station is crowded).
Taxi services: I do not even know how to use it.
Free parking in Ashford and Brussels: how cool
Nothing to write home about...