Ash body, heavy bridge, "vintage" headstock and lefty too! What more could you ask for? If it were mine apart from trying some of my favorite brand strings and checking the setup, a copper foil shielding job in the cavity is usually a good first mod. It will quiet the hum down quite a bit. OF course the SX pickups are single coil so the single coil hum won't leave if you select just one pickup. I wouldn't bother changing the bridge as it will mostly be just a change in looks. You did good!
A series-parallel mod is also a good thing to try on these basses.
