Nope. Not at all. In fact, many attorneys prefer that the other side file as the Plaintiff because they are required to present evidence and testimony first in a trial. In my experience, it makes very little difference who the Plaintiff is or who the Defendant is. I believe that most people mistakenly believe the term "Defendant" is negative because the term is used in criminal proceedings.
The only time filing first may be an issue is when an attorney believes he or she needs to freeze bank accounts or needs to file an emergency motion (more on that later...)