I guess you are going to memphis. Anyway regarding health benefits, there are a bunch of national plans (BCBS, etc.) and there are some state specific plans. I work at ZME and live in MS. I have BCBS and it is pretty much taken everywhere around here. They have Basic vs. Standard, and even though they sound the same which ever is more expensive generally has almost no co pay or a smaller co pay and covers a higher percentage of things.
TSP is a good investment, generally because the FAA matches 5%. Even though technically I think they match your first 3% dollar for dollar and then the next 2% they match half. So you put in 5% they put in 4%. Other than that if you are into choosing mutual funds and investing, then obviously the TSP is limited in what it can do. If the market sucks you drop to the G fund which is basically automatically gonna make like 1% or less. When it is going better you move to the other funds that will be more aggressive.
Best advice is to atleast put in 5% to get the max matching for the FAA. Then as you get more comfortable in you finanaces max it out when possible. The key is that it is taken out before taxes, meaning that if you put in 10% you really are only losing 7% in take home pay.