You should probably keep a few things in mind:

- first and foremost, FFPs are things designed by airlines to lock you into them over other airlines regardless of price. If you are an infrequent flyer and you can't have miles / status across several airlines / alliances, pick one but don't let it rule your life / spending / travel habits - then you won't be disappointed when it doesn't deliver a RTW First Class trip after a couple of domestic flights

- ultimately it depends on what you want out of the program. The best value out of a FF program comes when you can redeem for Premium tickets, not economy tickets. If you don't fly frequently, it would take you a long time to accumulate enough miles through occasional flights and credit card spend until you have enough for return business class flights.

- you say you don't fly much so it may not be worth you chasing status, particularly if you are used to flying Southwest and don't really have any status expectations. That said, there's no airline like Aegean in SkyTeam in terms of easy earning of status (there may not be in Star much longer, if a thread in the Aegean forum that it is rumoured to be converting to a Low Cost Carrier and leaving Star is true). The closest thing is probably Middle East Airlines which has a 40,000 mile requirement in 12 months to reach SkyTeam Elite Plus, but they have only joined ST so there's not been much discussion on here about how easy it is to earn and redeem on them

- MSPEconomist's point around the benefits of selecting DL is definitely true, particularly if you earn Silver status out of this trip. Plus you can get the DL Skymiles Gold Amex which gives you priority boarding and free checked bag with them domestically in the US even if you don't reach Silver status, and you earn miles on your spend. Problem with DL is that their redemption rates can be very high, particularly on their own metal. I live in Sydney and I get great value out of them because for 150,000 miles I can fly return Business Class Australia-Europe on one of their Asian ST partners, but that won't be much use for you based in Atlanta.

- Another option would be to credit the flights to Korean Air's program. When you fly DL you can credit the flights to them (L, U, and T fares on Delta earn 100% miles on Skypass). Their redemption rates aren't particularly low and they also have high season rates - however they have First Class which you can't redeem Delta miles for, only Skypass miles. And after you have flown 500,000 miles on SkyTeam airlines, you get lifetime SkyTeam Elite Plus status with them. You can also credit Alaska, Hawaiian and Emirates flights to their program. They also have a Visa credit card in the US which currently has a 15,000 mile sign-on bonus and 1 point per $ spent - http://www.skypassvisa.com/credit/of...=nm466&lang=en