Many choices between Economy and First! Business, World Traveller Plus (Premium Economy on BA), and on AA you have Main Cabin Extra which is a supplement on Economy, not available on all routes - don't think FCO-PHL has it.
You might find Iberia more comfortable for the outbound, as they have a nice 2-4-2 cabin in Economy. Perhaps ATL-JFK/BOS/MIA-MAD-FCO.