Torsten Kerl -- the Emperor -- is probably most affected by this, for notwithstanding his general aural appropriateness he's a bit too regular dude for the part. This is where the revival's cut of the Emperor's horse really hurts: with neither that big visual cue nor much clarity of personal interpretation, and with an unusually firm and forthright Barak in Johan Reuter, the distinction between Emperor and everyman -- their different roles in the story/allegory -- is lost. But Schwanewilms isn't helped either: the arm-waving she really really seems to like (her return show after Miller's appearance erased any doubts about that) needs to be either reigned in or connected to other elements on that side of the show, and there's no one to do that.
Meagan Miller, on the other hand, found in the lack of overall Emperor-Empress conception the opportunity to shape the show herself. Her alternate-cast Empress last Saturday offered a much clearer character trajectory than Schwanewilms' in the other performances, with the shock of having to become a morally responsible being coming, rightly, in bits through to the agonized spoken climax (where Schanewilms, relentlessly flighty before, incongruously springs a fully-trained philosopher-cum-rhetorician -- and yes, this is partly Hofmannsthal's fault, but one must make sense of it). And so though she sort of crashed into tough high stuff (like the D) where Schwanewilms more artfully ducked, and though her voice had some unsettlingly broad vibrato/wobble like Irina Lungu the night before (I don't remember this quality in Miller's Danae at Bard a few years back, so was she perhaps improperly compensating for the big house?) Miller was simply a more successful Empress than Schwanewilms, one around whom the show better and movingly built.
The difficulty Kerl, the director, and some of the less-gruntled viewers may have had stems from the fact that the Emperor, despite his title, is a LESS worldly figure than Barak, not more. Barak and wife are, despite the fantastic setting, rather familiar figures from the world -- you may recall their spinoff opera, Intermezzo, which Strauss wrote immediately after FroSch. The titled characters, despite such titles, aren't. For there is never a question of the Emperor ordering Barak or anyone else (besides the Nurse) around, nor any suggestion that he's a good, bad, indifferent, or indeed any kind of ruler: his title and position are only there to insulate him from everyone else.
What the two couples embody isn't so much positions in the world as positions of the world. For the Dyers it's all-too-close, and their faults arise therefrom: Barak too much mistakes his wife for the (rest of the) good in the world, and she mistakes him for the bad in it. For the Emps it's far off, vague, and so their troubles are more unmixedly within -- and in the immense space between even lover and beloved that Hofmannsthal's symbolist colleagues (and he himself -- note the lovers' quarrel in Rosenkavalier Act I) had worked so hard to open out.
And indeed there is -- and should be -- more Rilke than Siegfried to Hofmannsthal's Emperor. He is, near-fatally, something like the ideal appreciator of the Empress as she is, his hunt spiritual & symbolic -- the play (as he states up front) of his desire for her. What intoxicates him is that he can continue to pursue her, seemingly without limit: despite nightly consummating their union she remains... not virginal, exactly, but mysteriously integral without end in her pre-lapsarian perfection. (Last time I called the Empress sister of the Marschallin, Countess Madeleine, et al., but she is, to start, perhaps even more akin to Maeterlinck and Debussy's Melisande -- opera's most strikingly evasive amoral heroine.) It was, we may note, the Falcon's temporary breach of this perfection that angered the Emperor even though it had thereby won her for him.
It's Ariadne auf Naxos (going one opera backward in the Strauss canon instead of forward) rather than Intermezzo that illuminates the trouble here: if the magic of transformation is, as the Composer there unforgettably sings, the secret (mystery) of life, that is also what the imperial couple have rejected in their endless honeymoon. The Empress mentions a shape-changing talisman, lost in the "drunkenness of that first hour", but it was not only her form that was in that moment fixed. Both of them have cooperated to prolong that decisive hour indefinitely -- through to the start of the stage action proper -- down to their set roles therein: he in pursuit, she passively content after the rush of flight. (Compare, incidentally, how the action opens on Lulu and Dr. Schoen's marriage -- n.b. her animal metaphor!) The world threatens to eclipse the Dyers' individual selves, but their counterparts above allow their present selves to eclipse the world -- the perogative, for a while, of the rich or solitary.
But in life as in this story, it takes more than mortal resource to continue the same way forever. Only the divine and aesthetic may do that -- for mortals the only permanence is death... or ossification. In the terms of the tale, the Falcon's swipe had already brought Keikobad's daughter over to the side of the mortal/transient/disintegrable, and it was foolishly blind of the Emperor to continue to pay her homage as if it had not, as if she could have been brought into his grasp any other way (that is, in her original mythical form). Nor can the daughter/Empress, as she perhaps hopes upon hearing the deadline, go back to flitting in animal form while still retaining her husband, no more than her fixer could in any non-abominable way arrange for her to have the sign of mortal transformation (the shadow) without (as the Nurse so strongly advocates in their Act III argument) in fact changing anything else. The entire stage action occurs, for the married pair, in the hyper-prolonged moment of their decisive meeting, with the identities of Keikobad's (more or less divine) daughter and the (more or less mortal) Empress temporarily and unstably coexisting... so that resolution requires one to take the fore. And so she becomes the Empress proper, embracing transformation for both herself and her husband...
But the Symbolist angle tells us something else -- perhaps a why. If Emperor and Empress are recognizable, in their respect for mystery and inner space, as the symbolist poet and his ideal, their story seems not only exploration of a particular personal dynamic but critique of an aesthetic that Hofmannsthal famously mastered and even more famously (in English-speaking countries, anyway) left by forswearing lyric output for the stage.
Symbolist output of course has its own internal logic, but from our distant vantage it's perhaps most usefully viewed as a late station in the history of Romantic subjectivity -- or rather the scenes thereof. For the Romantic self was born in the Edenic no-place-in-particular which one might call "nature" by day and "night" by dark. But it had, after a while, to find its place in the world, and within mere decades had settled into alliance with the "civilized" against the proto-modern developments that were transforming the great and small facts of not only American but European life at the time. (This long-ago-forged inclination to the side offering to save collective meaning from the cold, alienating forces of arithmetic and cause&effect unfortunately continues to stultify and impoverish creatives to this day.) So as resentful and pessimistic as the portrayals of this late 19th-century milieu and its fantastic cousins became, there was, for these late Romantics, no getting away from it for long.
It's at this late juncture that we find the symbolist move -- to strip away the temporal elements of the scene. That meant, of course, the recognizably contemporary elements could be dropped, but not only those: in more sophisticated works place and time themselves fade from the scene as do even, at the limit in Mallarme et al., the particular identities of poetic self and its object. And so in, for example, Maeterlinck and Debussy's symbolist masterpiece Pelleas and Melisande, we see subjectivity's last form before it would return both bolstered and permanently sidelined (compare Alwa to Pelleas, Wozzeck to Golaud) by modernism... alive, as at its early-Romantic birth, in a no-place-in-particular, but now one in which interpersonal communion (or even, with Yniold or Hofmannsthal's Lord Chandos, communication) is infinitely difficult rather than Edenically obvious -- and the distance and stasis thus sustained is simultaneously despair, glory, and protection from the modern(ist) tide.
And yet this timelessness, too, was an artefact of its time, of the deep backwards leisure sustained in Vienna or willed in Paris, and could no more sustain itself indefinitely than the Marschallin could by stopping her clocks. So whether it was aesthetic, philosophical, or historical (it was, as many note, a WWI work, premiered in 1919) reasoning that brought Hofmannsthal to its birth, Die Frau ohne Schatten shows -- finally -- not just the melancholic presentation/renunciation of this anti-temporal perspective (Der Rosenkavalier, 1911) nor its transformation by stage-magic from the negative permanence of death/isolation to the positive of literal divinity (Ariadne auf Naxos, 1912/1916) but its full re-entrance into the change and renewal of mortal existence, bringing the Empress from beloved and bride to wife and mother and the Emperor from seeker to father. (Wernicke's restoration/glorification, at the end of the original production, of the Emperor's desire-in-action -- the Falcon, who precipitates the action of backstory and story -- brought this strongly to the fore, and its cut by Smit in revival was a huge loss.)
Whatever flaws this incarnation had, a good FroSch is unique in the canon of not only Strauss and Hofmannsthal but opera generally. With luck we won't have to wait another ten years for the next revival.