I like academic work, and I am fairly good at it, but not good enough to get on the tenure track. Postdoctoral salary for me is sufficient to comfortably support a family of four, and we don't mind moving from time to time, since my wife is not working. Is expecting to work as a postdoc for the entire life unrealistic? I know that some countries/universities only offer postdoctoral positions for up to 5 years after a PhD, but I have also heard that there are several other kinds of positions (i.e. research assistant, research associate, research scientist) that can be similar to a postdoc in everything but name. What is your opinion?