I didn't think the intro was too long at all.
The rainstorm and the flute were very nice and the drums + baseline did fit very well with the song.
However, there was something about the drums I found a little rough to go with the quiet background. Maybe too much snare? A slightly more definite sound could have been better.
That's only my opinion though, it was very nice.
One last thing - the rain goes on for way too long at the end =/ It would be fine if it was just ambient music but as a song, it's just too long.
Good job =)