Well, you can defiinitely get a different sound with a different mic, just not sure if it's going to be better. There are so many things that go into quality of the vocals that changing the mic might not help.
The first place to be looking at improving is the singer. Is he putting everything into his performance? No power or boom, hollow and boring seems like things the singer can improve on. Then you have to look at your room you're recording in. Is there treatment to minimize room modes, standing waves, resonance, etc. If not, it can cause a boxy sound with your vocal take. Then you can look at what you do with the vocal track after you record it. Over processing can kill a good take just as easy as under processing. Sometimes the simplest adjustment is all that is needed; a little eq cut around 600hz or something... you have to experiment to find what your voice needs, or doesn't need. Reverb: A lot of people use way too much. Here's a trick, dial in enough to sound good, then dial it out until you just can't quite hear it anymore.
Lots of things to do before looking at your mic. That Nady you have looks like a stage condensor (battery powered is okay, no phantom power necessary=cool) and probably sounds halfway decent, at least for the price.
And of course, we can only speculate without hearing a sample of what you're talking about.
good luck