I think Aeroflot's program is the only one that has their ST E+ at 50,000 miles per year, which means lounge access for less miles flown per year. However, I believe they require that you fly at least 30,000 miles with them specifically in order to qualify. KE Morning Calm Premium Club takes 500,000 EQMs (ST E+ too), but you attain that status for a very long time, longer than the usual annual expiration. If you are based in the US consider NWA or CO because their reciprocal mileage program allows you to double dip on EAUs (really nice!). And CO allow you to get EAUs on Copa and likewise with NWA and Alaska Air (for AS I think they give you certs and after that you can request at the gate) I really think CO is the best of the domestic airlines, they fly the most places internationally as well have the best domestic service and phenomenal premium cabin service. However, it obviously has a lot to do with location too!