I didn’t have very much work experience when I applied to the GSB. My resume was filled up mostly by a variety of summer internships that lasted about two months and school-year jobs that were only a couple of hours a week.
The good news for me was that all of my jobs made sense. I started with a job, realized what I liked about it and after the summer/school-year was over moved on to another job that was a better fit. Then I did it again. And again. All the jobs were in one sector and even though they were at different organizations my responsibilities kept increasing. Basically I was able to tell a story through my work experience that explained how I had developed my goals.
My understanding is that the GSB, and other business schools, are not looking for applicants with the most impressive jobs. Rather they are looking for applicants with the most impressive jobs relative to their peers given their history. So for my age a string of internships at unknown organizations was acceptable. For someone who graduated 5 or 6 years ago it probably wouldn’t be.
Similarly, schools want to see growth. For me, switching to a new internship with slightly more responsibility (even though I had no direct reports) was growth. For someone who has been in the workforce for a decade short-term internships won’t cut it. If you’re unsure, try to benchmark yourself against your peers, especially peers who have successfully applied to bschools. That should give you an idea of where you should be.
To summarize, I think you should try to use your experience to tell a story. It’s even better if it’s an impressive story given your age and experience.