For itineraries that require a connection, if I am traveling in J, I seek the routing with the most uneven sector lengths (so I have the greatest uninterrupted sleep time on the long sector). If I am traveling in Y, I would seek a routing where the two sectors are most equal -- to give me a standup and walk-around break in mid-trip. So for you, Y would suggest TK or one of the Gulf carriers; while J would suggest a European carrier.