I see no harm in working with State Farm for a year or so in order to get good agency experience. Learn what you like and what you do not like. Keep in mind though that any business that you generate through SF does not belong to you, nor does it belong to the SF agency owner, it belongs to State Farm. With that said, it's probably not a bad idea working with an experienced agent for a while.
Maybe you may decide that you want to be a SF agent. I know a SF agent and I am good friends with him, however I would not want to join SF. First off, I feel I can better serve my customers being able to represent the best company that will favor their case. When captive with SF or any other company, you lose that competitive edge. I don't want to make this seem like I'm anti-SF, but I just want to help you see the big picture.
Many agents start out captive and learn the ropes. There are certainly advantages with working with a company like SF, but they come at a price.
I suppose the big question is - What are you looking for? You may not exactly be sure yet. No harm in working for SF until you figure that out. Are you looking to run a service-based P&C agency with life insurance on the side? SF may be perfect.
If you are interested in Life (or health) only, I would not go to SF. You can achieve much higher commission and own your clients if you get hooked up with a good
IMO/
GA. You can get paired up with an agent who can train you. These days, training can be done with technology - internet, web meetings, etc... You won't get the salary, but you will make more money in the end.
Running a SF office is a huge undertaking, so if that is the direction that you want to go, be careful. Many agents have had financial devastation going this route. Not worth the risk in my opinion.
Upon reentering the insurance business, I considered opening a SF office, but quickly changed my mind. Instead, I chose to work independently. My monthly expenses are very low (E&O, leads, phone, internet, software, etc...) and my return on investment is high. I can work from anywhere - whether at my primary home in PA, my second home in Las Vegas, or anywhere else for that matter. I have true freedom and mobility, which is important to me. But these were my requirements. So, again, ask yourself, what do you want? Just because you are new does not mean that you need to work for a SF agency. But it could give you some good experience regardless.
Good luck!