PPErsonely I think part of your problem is the 5W30. Try a good 5W40 like Delvac-1, Mobil 1 SUV 5W40, Redline 5W40 etc.... TO date my 2AZFE has used 1/3 of a quart in 6000 mile OCI. IT was the first use of synthetic and that 1/3 of quart happened like the first 1000-2000 miles into the OCI. Since then I have not used any oil at all. I getinto the red all the time, downshift for engine brakeing and do a lot of WOT!!!! I drive my Camry like it is a rally preped Celica or Carolla!
I am currently running Redline 5W40. I am going to use Castrol Syntec Blend 15W40 in it at todays oil change.