Sounds like the OP is not elite on any airline yet. He says he'll qualify for DL SM by the end of next year (although OP, check your math again--if by flying 4 times per month you mean 4 trips per month (i.e. one per week), you ought to be able to qualify at least on segments a lot faster--that's a minimum of 8 segments per month [more if you're on connecting flights], which should get you to SM--30 segments--in less than 4 months).

Another idea (as a shortcut to elite status) that may or may not work: complete an AA challenge and then use that to status-match over to UA (if you're enticed by E+, where you're virtually guaranteed a roomy E+ seat) or to DL (which might be more convenient for your travel plans, but seating options with extra room are more limited). I don't know if DL or UA will accept a status match from an AA challenge, but it might be worth a try. (UA appears to have their own "challenge" available that combines E+ access and a "fast-track to elite" program, but at $799, it's kind of expensive).