Offered an agency position with 6 months of experience

Only if you feel unqualified now and believe you will be qualified with the added six months experience. It is totally up to you how you feel about going into the new job.

You feel confident after 6 months of experience?

Is it agency at one particular hospital or will you be expected to go to other hospitals?

Just understand that as an agency nurse, you will be expected to hit the floor running. I would encourage you to be open to asking questions of the regular staff, and let them know that you are there to help them and make their jobs easier. I do per diem for a larger agency and this attitude has help me. Also, you should absolutely carry your own insurance. Protecting yourself and your family should always come first.