<p>One argument for slowing the process down might be the opportunity to do research with a professor if you weren’t taking such a demanding courseload. Even though you’re already “in” the grad program, having some research experience might give you a step up later on (and you did say money wasn’t an issue).</p>
<p>If money is not an issue, then another option is to plan for four years, but enrich your schedule with additional courses that you are interested in, if you feel that you can handle the higher workload of taking more than 15 credits per semester.</p>