Yeah I noticed that one too but I love there version of one winged angel. I now have three different versions of it and there all good in there own way.
Its a great song for a video game song. Nevertheless it gives Sephiroth an extra mark on the badass chart. However, I like the music in Beyond the Wasteland, but then again that's because I've heard OWA and remixes of it like 1000 times.
kefka was an interesting boss, but is nothing compared to sephiroth. i liked kefka's music, very fitting and catchy. i heard some good remixes on his theme. the credits theme is usually always one of my favorites on any ff soundtrack. a little mix of everything. i typically like the piano variants..
i saw some piano sheet music for owa. insane. only a computer could play that crap.