Why stage a stiff opera about half-frozen royals by a not-yet-divine Mozartino? The best Mitridate really deserves is one of those intimate concert performances with brilliant young singers at which Ian Page's Classical Opera excels.

Der Rosenkavalier, you might think, is one of those operas that belong in a specific place and time and no other. “In Vienna,” says Strauss's score, “in the first years of Maria Theresia’s reign” (i.e. the 1740s). But this, of course, is a provocation.

Is it always the same bit of Cornish clifftop they gallop along in Poldark? Anyway here it was again, raising the curtain on the third series. As the camera flew in over a gaggle of squawking seagulls spiralling above the foaming surf crashing on the rocks, we could discern a lone horseperson charging across the skyline.

"Love is in the air," croons or rather bellows presenter Juri Tetzlaff, getting his audience of adults and children to bellow back the wordless refrain, arms swaying above their heads. Mezzo Sophie Rennert, dragged up as noble Lotario, and soprano Marie Lys as widowed princess Adelaide dance tenderly to the strains. They're not singing one of the most ravishing love duets in opera this morning because this is the one-hour family version of Handel's Lotario.

Even today, the perception of Venice as a city only half-rooted in mundane reality owes a great deal to Canaletto (1697-1768), an artist who made his name producing paintings for English tourists visiting Italy in the 18^th century. Recognisable views are subtly altered, the gently improving instincts of the artist shifting the scene almost imperceptibly away from real life, and into the realms of the imagination.

Enlightenment is a wonderful idea, and the members of the Orchestra of the Age of Enlightenment who played Bach’s six Brandenburg Concertos in Manchester’s Bridgewater Hall last night brought the wisdom of today’s period instrument movement to bear on music that most would see as belonging to the age of the pre-Enlightenment. Present-day enlightenment lies not just in historical accuracy, however, but also – from an audience point of view – in catching the spirit of its original creators.

Anyone who missed the opening Southbank concerts of the Chinike! Orchestra, figurehead of a foundation which aims to give much-needed help to young Black and Minority Ethnic (BME) classical musicians, could and now can (on YouTube) catch snippets of the players in action on the splendid documentary about young cellist Sheku Kanneh-Mason.

The social permutations of love are beguilingly explored in the 90-minute stage traffic of Marivaux’s The Lottery of Love, with Paul Miller’s production at the Orange Tree Theatre making the most of the venue’s unencumbered in-the-round space to dance the action along at a brisk pace. The only adornment in Simon Daw’s design is an elaborate chandelier, bedecked with candles and hanging roses, but the sheer élan of the piece more than occupies the stage in itself.

A wife dies to save her husband; a hero goes to hell and back to retrieve her from the underworld. Nothing of this dark myth, other than a rollicking row across the Styx from a bass singing Charon, ferryman of the dead, remains in Handel's incidental music to Alceste, a play on the subject by Tobias Smollett (of Roderick Random fame) which never reached a putatively extravagant Covent Garden staging and which has vanished from sight.

The annual London Handel Festival is dutifully working its way through every one of Handel’s operas in a cycle that will eventually take us from Alcina to Xerxes before, presumably, starting all over again. But each year, alongside these headliners, we also get a pasticcio – an opera stitched together by Handel from the shiniest and most decorative musical scraps by his European colleagues.