IL PRATO DI PACE MIO: it's well adjusted to the soprano tesitura. Perhaps it is most of the time in the middle-upper register La3-La4. I think the lowest note is a F#, which is OK. The highest note is a B5 in m. 60, a note that a concert singer can reach. It sounds baroque 100%, only that the highest note is usually in the last part (or it is the last note).
SLEEP MY CHILD: perfect! There is a Bb4 in the first part, but in the repetition it's a C5, which is the top note I would write for an average lyric sopran, or spinto. Higher notes are reserved for coloratura soprans, and in this case you must be careful with the lower notes.
LENTAMENTE, I PRIMI FOGLIE VERDE PALLIDO APPAIONO The question here in my opinion is that the voice is in the higher range too much time. That's too tiring for a singer. With a flute it's easy, but... I mean, the range is OK (top note: C5, although it is present in the first part and in the last), but I think you should use more the middle range, which is almost always the strongest in the singers. The quick part is also typical.
PER DOVE IL NOSTRO MARINAIO VA This is also OK, from a C3 to a B4 (I think).
In summary, it's a wonderful sets of songs, in this baroque style. You manage quite well the voice, it's difficult to do it (I'e never tried, but not sure I could). The melodies are nice and the ornaments too.
This would be a fantastic start point for an "album" with this kind of aria. The other type of baroque aria is the bravura aria (you know, very quick and with a "stronger" singing). This set you've written could be seen as bel canto arias, if the piano was treated in a different way.
There are many resources you can use in this writing (accents, etc...). I don't know if you have studied (simply listening to the great singers and following the score in you tube). You can learn a lot doing that. You'll notice that some of the best arias don't reach very high notes (for example O mio babbino caro, everyone knows it, reaches Ab4 several times, but no more).
Farther, there are arias, of course. But just a few singers can do Poppoli di Tesaglia, Io non chiedo by Mozart in which the sopran must sing a G5 twice. This aria was not for an opera, it was written for a specific sopran (Aloysia Weber). I think the G5 is also written by Richard Strauss for the Zerbinetta role. F5 appears in the aria of the Queen of the night (Mozart, The Magic Flute). Eb5 is more frequent, but sometimes it is indicated as optional, as in La Traviata, Sempre Libera (end Act I) where Verdi wrote an optional Eb5 (if the sopran can't do it, then a C5).
Now and then an incredible singer can do EVERYTHING: coloratura, dramatic singing, wagnerian.... Callas and Caballé (they sung from Wagner to Haendel, Bellini, Verdi, Rossini, ...). Caballé didn't sung Eb5 (never, I think), Callas did, of course.
Well, this is an amazing world, in fact. I love opera, and I know many many of them, and many singers.
The case of the tenors is another world.
I would put here some examples from youtube. But this is so wide... And if you are interested its easy to find arias. Besides, some people don't like that other things are uploaded to their posts.
This work was done as part of my "quick write" challenge for myself, to compose often and in shorter time intervals to help eliminate the previously long time periods between composing works. I woke up one morning to some deeeeep thunder rumbles and the power flickering, combine that with a half note riff I worked up in the band room before I taught at school that day and PRESTO!! Instant "epic electronic hodepodge of stuff".
Let me know what you like and what I could do better--I'm not a mixer, these sounds are all done with the Sibelius sound library with minimal adjustments to anything........