Look. Do something, anything, because doing nothing tends to make you look like a serial killer, true or not. At that point, ecs really don't matter relative to your numbers, except for Yale and Stanford. That's it. There are a few outlying cases (eg: Data, last cycle) but generally speaking, ecs are not important. Do whatever you want. IM baseball is fine. You might want to add something if you also don't have any work experience, but that's only because IM baseball is not a huge time commitment (read: plenty of time for you to be serial-killing in the off-season).
Also: COLLEGE IS FUN. I miss it SO MUCH. HAVE A GOOD TIME while you're there. Maintain your numbers if law school is a goal, but other than that, HAVE FUN.