Just out of curiosity, why are you booking these as one-ways? They are really round-trips for fare construction purposes, or they would be on United... United considers FLL and MIA to be co-terminals, as well as HPN and LGA. Have you tried pricing your trips out on United? They might come out cheaper. There's also a double-EQM promo going on until June 15.

(That said, I don't know if there are non-stops available; you might have to use connecting flights if you want the trip entirely on one carrier.)