I wouldn't boost it with a Limiter. (I stopped doing this myself) To me, the mix is a tad bit louder than the vocal. I can clearly hear you, but it's under the music.
Do you have the song as separate tracks? I think if you just turn the music tracks down a bit.
As far as volume and dynamics in general (and don't take this full on), maybe you could use a compressor as a limiter (lightly) to boost the volume. In terms of where the TARG values should be, I'll leave that to Jeff, Beags, Danny, etc.
Or you could go back in the mix and HP the instrumentation, "isolating" the vocal and doing A/Bs.
Back to the Limiter though, I'd back of. I think it's a last resort plug and needn't be used if you can help it. Like I said, I thought Limiters were the answer, but at least for my songs, they are not. If you can turn up the volume by other means, that's probably the better route to take.
Again, I could be wrong. Someone correct me if I am somewhat off course.
Other than that, to me, I believe it is mixed very well.