The short answer is NO......a cheapish pre will not do that much for vocals.
To get a great studio recording you need a great mic...great interface and have a good PC with top end sofware capable of studio quality results...it all costs.
Recording with an SM58 or other dynamic is asking for trouble and no pre will get you out of that trouble. Adding stuff pre record rarely works out.
Keep the chain short and simple...and use the best studio mics and interface you can afford. Once you have a good dry recording then it can be edited and processed. Compression and fx can then be added.
All that said you need great engineering skills to produce great results. I have seen some bad engineers with the best gear available produce real turkeys and clever guys with modest equipment produce great recordings. Knowing your gear and knowing what to do with it is the key. It is possible to produce pretty good stuff with budget equipment providing you have the know how. Learning the art and having modest equipment is better than having the best but not knowing how to use it.

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