Agreed, it is a shame that they no longer do this. I suppose where the majority of aircraft are boarded nowadays via an airbridge, it is no longer visible to the customer so was dispensed with around the time of the T4 move.
The Vanguards carried their BEA names through BA as Merchantmen and then Air Bridge (latterly Hunting) carried the names on those aircraft they later acquired. They were EG = Arethusa, EI - Indefatigable, EJ - Ajax, EK - Dreadnought, EL - Leander, EM = Agamemnon, EO = Orion, EP = Superb, ER = Amethyst, ES = Swiftsure, ET = Temeraire, EU = Dauntless.
Piece of pub quiz trivia: the Vanguard names were all ships of the line in Nelson's time, with Swiftsure being a prize captured in the Battle of Trafalgar. I can't even begin to imagine the sense of righteous indignation from the SNP if British Airways named its aircraft after our Trident-carrying nuclear subs today - it's almost worth doing it just to provoke an apoplectic reaction from Sturgeon and Salmond.