Hi, Beth.

Regarding your three questions:

Is the hissing of the flute too annoying? Is there anything I can do about it?
The version I heard has the flute too far in the background to even hear any hiss. I didn't even remember hearing it once the song was done.

If you've got issues with flute hiss, you can use a low pass filter to cut off some of the high frequency noise.

Do the congas work or is it just messy? I could not find the drums I wanted. I'm open to suggestions if you think something in the Pro pack could work.
Drop the congas, they don't really add much.

What genre would you call this?
It's folk with New Age lyrics - at least, that's what an average listener would discern from the lyrics.

-- David Cuny
My virtual singer development blog

Vocal control, you say. Never heard of it. Is that some kind of ProTools thing?