If I switch my LLC to an S corporation, will that limit my tax burden?

You should consult a tax attorney or CPA with experience in dealing with business formations. Although, the LLC should be better in theory with p-through taxation. A S corporation could be beneficial if you were looking for a way to raise additional capital to expand your business. However, you should consult with someone to consider the specifics of your business for a proper evaluation. There are other issues besides tax liability involving those structures that should be considered as well.