2009 mazda6 s. 180,000ish miles, all stock. I didn't have oil issues until recently. No drips. Oil light will blink on every now and then so briefly it's hard to notice.
Have you ever replaced the PCV valve? If the spring on it is wearing out, that could be letting too much oil from the crankcase into the intake. That would be my first step, since it's such a cheap part. I know all PCV systems have the potential to let some amount of oil into the intake, but anything else would be beyond my limited expertise.