Speaking from experience, starting characters should not be as powerful as cannon characters. Later on though they could rise to the challenge. Many of the characters in our series are great characters.
One of our PC's, Nathan Mcguillan is a Commander on the U.S.S.Andromeda. He's a veteran of the Dominion war, decorated more times than I can remember. Fought in the 2nd Klingon civil war and was in Voyager-like situation for two years. His skills and experiences, along with the friends and enemies he's made have made his a character on par with Spock and Riker. A famous 2nd in command who doesn't want to be in charge.
"The misery of being exploited by capitalists is nothing compared to the misery of not being exploited at all."
-Joan Robinson, economist