If the F2M singing the Queen of the Night does HRT, he's probably not going to be able to sing high Fs for much longer.
I still have never seen
Rusalka.

I looked at the cast list, and the only singer I was familiar with was Jill Grove, who sang Jezibaba the witch. How was she? The one time I've seen her, she was terrific.
I know what you mean about operas seeming too long. Did they get paid by the length of the show? No, but most of them were written before radio and TV, and they were expected to provide a full evening's worth of entertainment. Also, once music won out in the struggle over whether the music or the words/drama was more important (and yes, for the first century or so of opera's existence there was an argument over this), composers got the excuse to stretch things out beyond what would be dramatically interesting. Sometimes the music is worth it, sometimes not.
You do know, don't you, that there's still opera being written today? Some of it is even good.