Your sound is actually going to be more affected my your mouthpiece choice than your instrument choice. I could play on a cheap student sax with my good mouthpiece and sound great. But give me a crummy plastic mouthpiece and the best saxophone on the planet and my sound will not be so great.

So, I would first make sure you have a good mouthpiece before you start looking at a new horn. For your playing venue. If you dont', I would recommend looking at a Vandoren Optimum or Selmer C* mouthpiece. Also, BG has just come out with a nice classical mouthpiece. These are all available at great prices on Saxquest.com. 

Also, assuming your current saxophone is at least functional, I would wait to purchase a new saxophone until you've been playing for at least a year. This will allow you to develop as a player to the point where you can adequately judge for yourself the subtle differences from horn to horn. 

Cheers,

     Mark Overton

     saxquest.com

Get you a vintage c-melody saxophone for church and experiment with different alto mouthpieces. Out of this world. I have rebuilt and sold to date about 25 of them and they all have been great players no matter who made them. They are just effortless to play. Don't use the c-melody mouthpieces that comes with them because they are all terrible like blowing into a stopped up water hose. God Bless and good luck on your quest.