Well, aside from a cure (or more effective treatment in general), I think there are definitely some other areas that could be beneficial. For one, an easier and quicker way to diagnose MS would be extremely beneficial. There are many people that end up taking way over a year to get diagnosed, which is a lot of time for them not to be on any treatment and ultimately impacts their level of disability later in life.
Other areas to research that I think would make a big impact are fatigue and mental health, both areas plague people with MS and both tend to have very few sources of relief. Improving either area would really improve the lives of those with MS.