Many students find this to be a good idea. One may have more to show after working in a field related to your major. They look for strong students who know what they want in their field. Research is valued as well as internships. Evaluations and strong grades play a major role, also high GRE's help but do not make or break you.
Graduate schools use grades as a dividing line, high grades show strong study skills.
A GPA of 3.00 is standard. Psychology has a strong liberal arts background and is a good start for other fields. Make sure you take the correct prerequisite for that particiular field. Thanks for your letter of March 30. After careful consideration, I regret to inform you that I am unable to accept your rejection at this time.