1) Take the vocals in this version solely to get the idea of the melody - I wasn't trying to sound great and I had a bit of a sore thought as well (as you can hear at "think twice")
2) What do you mean by the transition to the chorus - the actual beats themselves or the instrumentation on the whole?
3) This is the way the original singer pronounces "perfect li-i-ife" - I think it sounds odd to try and blend the vowel sounds together at that part, as you lose the accent on the note fluctuation (if that makes any sense to anyone!) It's also perhaps slightly more noticeable cos of my Scottish accent
4) If you're talking about the "chance - chance - chance..." echo, I wasn't sure about that at all - it was just an idea I had that didn't fully work as well as I'd hoped...
But anyway, thanks for the comments. Just so everyone else knows, I'm a lot more interested in what you think of the backing track and arrangement, as the vocals will definitely 100% change for the better
;