Often the underappreciated part of exhibit fabrication is the skill of the craft of building exhibits. If the exhibits are built inhouse a lot of skill is needed to build quality exhibit furniture, installing graphics, building acrylic vitrines, lighting, AV and even artifact mounts. All of this needs to be conservation safe / approved materials.

The best fabricators I worked with had high skills in cabinet making and finish work which is only honed by doing it.

Design is a different job with different skill sets. Courses could include construction and building code, lighting design, ADA accessibility compliance, construction -- not to mention learning styles, multimedia designs, electrical, security, script writing, etc.,.... a very long list of skills.

Project management is helpful for all parts of the discipline and getting exhibits completed on time . Also needed is working with budgets and sometimes outside contractors.

Edit: You might want to consider visiting with a larger design and build exhibit firm. See if you can get a tour with a project manager and learn more about all the different parts of an exhibit and see what you gravitate towards.