I think for graduate programs restructuring the course structure is a very viable idea. When I was attempting to create the grad program for IxD at SCAD back in ’09 I was trying to model it after programs like CIID and Umea that have a more flexible system like you’re describing. For CIID it is really easy to do this because tehre is only ONE program. The entire cohort is together all the time and the structure of classes has no interdependencies with other courses/programs at all.
For undergraduate courses especially there are lots of interdependencies for sure. You have some sort of foundation, you have double-majors, you have general studies, and you have cross program electives. Not to mention schedulign against holiday periods so that students can compete for internships and co-ops.
For many graduate programs being able to take cross-department courses is also very important to the success of many design programs. I’d also add, it is the value add that they bring to their programs.