I agree that that's a pretty good route you've scored. If you can't deal with the timing, and willing to spend the AMEX money, have you checked availabilty for the EWR-KUL Trans-Atlantic Flight on MH??
OR have you looked at the TG Trans-Atlantic via BKK, that flies all Economy Deluxe and Business and is in Star (don't know about upgrade options with UA miles and TG)