FDX has a very good jumpseat policy. You can reserve a jumpseat on one of our airplanes up to 3 weeks in advance. This allows you to plan how to get to work and not worry about it. You are also protected, within certain parameters, if your JS fails to make it to MEM.
Some choose to live in the MEM area, but it is a choice. I don't, and I have probably made less money and been gone a little more than those that do, but it is a trade off so my wife can live where she is happy.
If you are within an hour or so of an airport served by FDX, you can live right where you are right now.
If you have a domestic schedule, it is sort of week on, week off. If you fly international, you might have one 12 day trip and then be done for the month. The single departure lines save time commuting, and give you more time at home, IMHO, but 12 days is a long time to be away, and you have less flexibility with your schedule. Smaller trips are easier to drop and trade, long trips are not.
Good luck with your decision, search past threads for more info.