It was a Disney theme-park of Russian music, and in an entirely good way: none of the usual rides, but plenty of heroes and villains, sad spirits and whistling witches, orientalia from the fringes of empire, pagan processionals and apocalyptic Orthodox chants.

There it gleamed, the pearl in the massive oyster of Albert's colosseum: the gilded, decorated piano supplied to his Queen by Érard in 1856. Pearly in sound it was not, though often harp-like; the programme was of mostly silver works, with a gold scherzo and some wooden songs.

Berlioz's most intimate oratorio certainly isn't just for Christmas – but, given its scale, is it right for the Proms? Certainly in anniversary year we'd hoped for something bigger: the Requiem, turned to mush earlier this year in St Paul's Cathedral, could have been made for the Albert Hall, with brass bands placed at the four points of the compass.

Perhaps those who came for the Argerich touch and left at the interval of this instant-sellout Prom were satisfied. After all, the legendary Argentinian pianist gave us some vintage minutes of her silk-spinning mercurialism.

The BBC National Orchestra of Wales’ second consecutive night at the Proms, accompanied by their associated National Chorus, ventured further out of the classical mainstream than the first. Where Wednesday night had seen a solid Germanic programme of Brahms, Wagner and Mozart Thursday saw a British world premiere and some enchanting Japanese music, alongside two meaty Russian classics.

Not every Prom has to push musical boundaries or bust concert conventions. On the face of it, last night’s programme from the BBC National Orchestra of Wales (and National Chorus of Wales) stuck to a thoroughly traditional recipe. Two familiar 19th-century orchestral warhorses cantered out for the first half, followed by a beloved choral blockbuster delivered by massive forces who engendered a big, hearty, hall-filling – dare I say Victorian? – sound.

It’s a curiosity of music that a performance can occasionally be better – more persuasive and impressive – than the work itself. Even Britten’s most devoted advocates would find it hard to rank the Piano Concerto among his masterpieces. In his account at the BBC Proms last night, however, Leif Ove Andsnes carved out a niche for the piece as a confident yet quizzical response to the genre, standing diffidently to one side.

Montrealers exude a particular kind of happiness and have wonderfully snappy expressions to convey it: “Chu correc”, means ‘I’m fine’, and “C’est l’fun” means...exactly what it looks like.

Messiaen’s language of juxtaposition over development was always susceptible to the “greatest hits” phenomenon that began to suffuse his music with contented wonder during the 1970s. While younger colleagues were throwing toys out of the pram and marbles at walls during the late 1960s, he was putting heart and soul into a synoptic concert rite – part concerto, part cantata, all-consuming – based on the Transfiguration of Jesus.

By happenstance, this Prom was fully topical, with Debussy’s languorous Prélude à l’après-midi d’un faune fitting for one of the hottest days in London’s history, and the “Infernal Dance” from Stravinsky’s Firebird mirroring the infernal political dance taking place simultaneously in Downing Street.