There is very little overhead, so if you have a complaint about a coworker's performance affecting your clients, good luck.
Upper management is disorganized and has unclear expectations and rules about sick leave, PTO, and what is/isn't allowed during work hours. I never got an employee handbook, and was unclear about how to ask for time off, or go home early if I don't feel well. I constantly felt like I would get in trouble if I requested time off "by the book," even if it was completely justified.
I also felt stuck. After three years, I got more responsibilities and raises, but my title never changed. I still had an entry-level title, with management responsibilities and salary. Since the company is so small, there is no upward movement and opportunities for managerial growth.