What Bitflipper said is exactly what I would also suggest.
Your mic is fine, your room acoustics seem fine too... and your voice quality is great! The reason it is not fitting into the mix is the subtle pitch fluctuations in your vocal. They are intricate and the interesting style is quite meandering and thus not quite on pitch.
Rather than investing in a new mic I suggest getting Melodyne studio 4 or Melodyne Editor.
Once your pitch matches the beautiful electric piano, it will nestle into the mix perfectly and step up front.
Then a little bit of compression and volume haggling on each syllable to flatten it out a bit and you are golden.
As Bitflipper also suggested, doubling a few choice parts here and there (usually chorus) with your voice is also a nice effect too.
Fix the pitch and the song will accept your voice as a lead instrument.
Your vocal pitch is fighting the song's tonal center. It will not mix in and step up front until this is corrected.
Best