I have the 05 Camry with the same engine and about the same oil consumption...I just stocked up on end-of-year/end of jug-design closeout synthetic...5w-30 Penn Platinum at $2/qt (no rebate here, after having to fight rebate central twice for my $10).
I just pour in a 1 quart @ 2k and 4k miles and change the oil and filter at about 6k miles.
I probably could leave the filter in there for 2 OCIs, but it's just too much of nothing to worry about...
I bring it to the dealer and for $20 they change my oil with either their filter or mine (I alternate Toyo's and mine bought on sale). That's about $38/syn every 6k miles OCI how ever many months it takes to do 6k miles...for the past couple of years it's been about 10 months.
I suppose if I drove 20+k miles a year I'd feel inconvenienced to have to add oil, but if I did run that many miles, most would be on the highway where oil quality is diminished the least, and so I'd likely stretch the OCI to 10k (@ $42/OCI)...but...
I change oil every 6k miles because most of those miles are short-run trips around town. I'm confident that adding 2 quarts over those 6k miles mixes in enough additives to keep the oil fresh for a 6k OCI.
I'm probably being overly conservative here, but for as cheap as oil is, I just don't see the need to stretch an OCI past 6k, let alone past 10k miles.