The London Handel Festival is back, and instead of ploughing their usual furrow of rarely-seen works, this year’s opera is a classic. If the rest of Ariodante doesn’t quite live up to the promise of its two often-excerpted arias (“Dopo Notte” and “Scherza Infida”), then it’s still a deeply satisfying evening of music, with a large cast perfect for showing off the talents of the Royal College of Music’s student performers.

Gluck's two operas about the daughter of Agamemnon saved from sacrifice only to serve as priestess-butcher herself have found their level on the contemporary operatic stage.

What a load of balls. No, seriously. Globes, orbs, moons, suns, juggling balls, beach balls, er balls balls: if it’s spherical and pregnant with symbolism then you’re bound to find it somewhere on the props table for English National Opera’s Akhnaten. At the centre of Phelim McDermott’s new production of Philip Glass’s opera is a troupe of jugglers.

Anyone who says Handel can’t do psychology should spend an evening with Orlando. Form, orchestration, even exit conventions are all reinvented or cast aside for a work of startlingly contemporary fluidity, where music is completely the servant of drama. Stripped back to little more than the score last night, in one of the Barbican’s very-semi-stagings, Handel’s emotional architecture was completely exposed, allowing us to see just how jaggedly inventive its lines really are.

Brand-new youth operas tend to fall into two types. One is hugely rewarding for the participants, a skill learned and a treasurable group experience to be remembered for the rest of their lives, as well as for their friends and family in the audience.

From working-class hell via convent purgatory to Florentine comic heaven, the riches of Puccini's most comprehensive masterpiece seem inexhaustible. In a production as detailed in its balance between the stylised and the seemingly spontaneous as Richard Jones's, first seen in 2011, there are always going to be new connections between the three operas to discover. Some things are stronger, some weaker second time around, but you still come away convinced that each work glows best in its original context, and that none should be prised away.

The third of Beaumarchais’s Figaro plays, La Mère coupable, is a very different affair from the other two, in that it records actual adultery and its disastrous consequences (including Cherubino’s death in battle), as opposed to the largely comic innuendos and mistaken identities of The Barber and The Marriage.

From the more or less inconsequential wit and bravura of The Barber of Seville to the profound comic psychology, social nuances and unparalleled musical genius of The Marriage of Figaro, and from the silly antics of Sam Brown’s Rossini to the style and brilliant stage management of Tobias Richter’s Mozart, is a good lesson in music theatrical history played backwards.

In the end, it’s all about the oranges. They adorn the programme that accompanies Harry Fehr’s intelligent new production of Handel’s Ariodante for Scottish Opera. More importantly, they’re prominent in designer Yannis Thavoris’s clinical steel-and-glass set, growing on carefully groomed bushes in six neat tubs, placed meticulously below warming light bulbs, protected from the gales and snow drifts outside by a wall of glass.

In the light of what follows, it's probably best to be clear that I'm completely behind the artistic side of ENO in rejecting a 25 per cent reduction of the chorus's annual salary, tied to a shorter season. A full-time chorus of this size is the heart of a big company – without it, no Mastersingers, no Grimes, no Lady Macbeth of Mtsensk. A creative alternative solution must be found.